Preseason and FIFA Club World Cup Following the end of the 2022 season, general manager
Garth Lagerwey departed Seattle to become president of
Atlanta United FC. He was replaced by technical director
Craig Waibel on November 30. During the offseason, the Sounders exercised their contract options on most of their roster with the exception of forward
Will Bruin and midfielder
Alfonso Ocampo-Chavez; defender
Jimmy Medranda was also released into
free agency. The club had 11 players with guaranteed contracts through the 2023 season, including most of their veteran squad. In late December, the club acquired forward
Héber through a trade with
New York City FC. Seattle also signed two
Homegrown Players, midfielder
Sota Kitahara and goalkeeper
Jacob Castro. The club's two
SuperDraft picks, forward
Eythor Bjørgolfsson and defender
Blake Bowen, were signed by reserve side
Tacoma Defiance after training with the first team. The Sounders opened their training camp at
Starfire Sports in
Tukwila on January 4, 2023, with a full roster of healthy outfield players following the return of
João Paulo and
Obed Vargas from their 2022 injuries. The team played several intra-squad scrimmages during their Seattle training camp due to difficulty finding MLS and
USL Championship teams with open schedules. The Sounders moved to
Marbella, Spain, in late January as part of preparations for the
FIFA Club World Cup hosted in Morocco the following month. There, the club was split into separate teams for scrimmages on January 28 against two European teams: a scoreless draw with
Wolfsberger AC of Austria and a 3–2 loss to Swedish side
Hammarby IF. Seattle entered the Club World Cup in the second round and lost 1–0 to Egypt's
Al Ahly, conceding a deflected goal in the 88th minute. They were the first MLS team to play in the Club World Cup and earned $1 million in prize money as a participant. The team were eliminated from the tournament, but a month later qualified for the expanded
2025 FIFA Club World Cup as one of four CONCACAF entrants—all recent Champions League winners. Following their return from Morocco, the Sounders played a closed-door scrimmage against
Louisville City FC of the USL Championship and won 2–1 with a set of rotated lineups. Several players remained in limited training through the end of February due to injuries and fatigue, including Vargas and striker
Raúl Ruidíaz.
February and March (pictured in 2019) became the first Sounders player to score four goals in an MLS match The Sounders opened their MLS regular season campaign on February 26 at home against the
Colorado Rapids. The team earned a 4–0 win—
Cristian Roldan scored the opening goal of the season and was followed by
Jordan Morris pair of headers. Héber also scored in his MLS debut for the club. Morris and Héber scored a goal each in the following week's 2–0 victory over
Real Salt Lake at home. Héber later suffered a hamstring injury during training and was replaced in the starting lineup by
Fredy Montero, who had returned to the Sounders on a renewed one-year contract. Seattle's first away match of the season ended in a 1–0 loss to
FC Cincinnati despite the home side earning a
red card. A late equalizing goal by
Yeimar Gómez Andrade was called off by the
video assistant referee due to a foul in the build-up. The team earned their third home
shutout in a scoreless draw with reigning
MLS Cup 2022 champions
Los Angeles FC. Ruidíaz returned to the starting lineup, but was substituted early due to injury concerns. The Sounders played against
Sporting Kansas City with several positional changes due to the absence of six players who had been called up to international teams. Jordan Morris became the first Sounders player to score four goals—all assisted by
Léo Chú—in the club's 4–1 victory, their first on the road since July 2022. The Galaxy cut the lead by a goal and made several unsuccessful attempts to score an equalizer; the team appealed for a penalty following an alleged
handball by
Nouhou in stoppage time, but were denied. Goalkeeper
Stefan Frei finished the match with seven saves and tied
Osvaldo Alonso for the most MLS starts in club history at 322 matches. The Sounders traveled to Portland and faced their
local rivals, the
Timbers, without starting midfielders Cristian Roldan and
Albert Rusnák, who were both injured. Ruidíaz scored the opening goal of the match in the 58th minute, but the Timbers scored four goals to earn their fourth consecutive win against the Sounders. After the match, Schmetzer called the result an "emotional punch to the jaw" and said that the Sounders "have to get back to understanding that this is a rivalry"; he also attributed the shift in momentum to his substitution of Léo Chú for Héber and uncharacteristic defensive mistakes. Ruidíaz suffered a hamstring strain during the match and was later ruled out for four to five weeks; Cristian Roldan, still under
concussion protocols, and left-back
Nouhou were also unavailable for the next match at home against
Minnesota United FC. Rusnák scored his first goal of the season in the 1–0 victory over Minnesota in the 79th minute, ending a defensive deadlock that had limited scoring chances for the Sounders. The hosts took a 2–0 lead over San Diego in the opening half-hour, but conceded a penalty in the 53rd minute that was converted by
Joe Corona. The Sounders reclaimed their two-goal lead but conceded twice—a free kick from Corona and a long-distance strike by
Kyle Adams in stoppage time—to finish regulation time at 3–3. In extra time,
Reed Baker-Whiting scored from outside the box for Seattle, but San Diego's
Jackson Kasanzu headed an equalizer shortly after entering as a substitute. Kasanzu conceded a penalty in stoppage time that was converted by
Fredy Montero for his second goal of the game as the Sounders won 5–4 and advanced in the U.S. Open Cup for the first time since 2017.
May The Sounders returned to MLS play with a scoreless draw against Real Salt Lake in Utah, where the team had only won once in fifteen previous regular season matches. Defender
Kelyn Rowe started the match and left in stoppage time with a knee injury; he had replaced Nouhou after the latter contracted
malaria. Defiance defender
Cody Baker was signed to a short-term contract to replace Rowe ahead of the next match at home against Sporting Kansas City, which the Sounders would play without the injured Roldan and Ruidíaz, as well as João Paulo for yellow card accumulation. Sporting Kansas City earned their first win of the season after scoring twice in the opening half-hour; Montero earned a penalty for the Sounders in the second half that was converted by Lodeiro, but the team lost 2–1, their first loss and non-shutout at home in 2023. A few days after their elimination from the U.S. Open Cup, the team traveled to play the
Houston Dynamo with both Baker and Rothrock signing an additional short-term contract to fill in for injured first-team players. The match was disrupted in the first half by a weather delay and included two red cards shown to Dynamo players; the sole goal in the 1–0 away victory was scored by Rothrock in the 87th minute. A total of eight players who appeared during the match against the Dynamo had been developed in the Sounders academy, setting a club record. The Sounders returned home to play
Austin FC, who snapped an eight-match winless streak with a 2–1 midweek win at Lumen Field; after several substitutions, Fredy Montero scored for Seattle in the 79th minute and the team unsuccessfully pushed for an equalizer. The Sounders then lost 2–0 on the road to
Vancouver Whitecaps FC, conceding a goal to
Pedro Vite in the first half and an
own goal by Stefan Frei in the second; the result dropped the team to second in the Western Conference. The Sounders began a three-match homestand with a 1–0 win against the
New York Red Bulls, who they played for the first time in four years. Morris scored the lone goal of the match in the 22nd minute, but was substituted three minutes later due to a groin injury; Seattle maintained a shutout despite losing João Paulo, who was sent off after receiving a second yellow card in the second half. In a midweek home match, the Sounders lost 1–0 to the
San Jose Earthquakes, who broke a 14-match away winless streak.
Jeremy Ebobisse scored early in the second half as the hosts made 23 shots that forced eight saves out of Earthquakes goalkeeper
Daniel. The team finished May still atop the Western Conference standings and only one home win in four matches at Lumen Field.
June and July On June 3, the Sounders and women's team
OL Reign held a
doubleheader event at Lumen Field, their shared home venue, against their respective Portland rivals. The clubs sold 42,054 tickets to the doubleheader, which began with a scoreless draw between the Sounders and Timbers; it was the 100th MLS shutout for Frei and also marked the return of Cristian Roldan following his concussion. After the match, Schmezter stated that the team had "dropped points" but he "believe[d] in the process that we have" especially as players returned from injuries; the Sounders had only scored four goals over an eight-match stretch that included four losses. The team then traveled to play
Charlotte FC with Roldan and Ruidíaz returning to the starting lineup for the first time since early April. The Sounders took the lead three times through a first-half goal by Roldan and a brace from Ruidíaz, but the match ended in a 3–3 draw. The team took a break from play during the mid-June international window and lost Jordan Morris, Cristian Roldan, and Alex Roldán to national team call-ups ahead of the
CONCACAF Gold Cup. The Sounders played mid-week on the road against Los Angeles FC and lost 1–0 after conceding a goal in the first minute and struggled to find a chance to equalize. They returned home and played
Orlando City SC to a scoreless draw to continue their month-long winless streak; Ruidíaz was absent for the match to attend a family funeral. The five-match winless streak for the Sounders ended on July 1 with a 1–0 win at home against the Houston Dynamo, who again had a player sent off. Rusnák scored the lone goal of the match in the 67th minute. The Sounders traveled to Vancouver for their next match but would play with goalkeeper
Stefan Cleveland replacing Stefan Frei, who had a concussion during training. The team won 3–2 after trailing twice against the Whitecaps and not earning a penalty for a potential handball in the box. Léo Chú scored two equalizing goals in the 60th and 76th minutes from set-pieces that were assisted by defender
Jackson Ragen's headers. The winning goal was created in stoppage time by Chú's cross into the box, which was deflected to reach
Yeimar Gómez Andrade, who scored from inside the box. In their second away match of the week, the Sounders lost 2–0 to the San Jose Earthquakes, who won the
Heritage Cup as a result. San Jose scored from a penalty kick in the 19th minute and a volley shot off a corner kick in the second half, while Seattle were limited to two shots on goal. The Sounders returned home to face
FC Dallas with their full contingent of starting players after the conclusion of the Gold Cup. The teams played to a 1–1 draw that began with an
own goal by Dallas defender
Sam Junqua and was followed by a
Bernard Kamungo header to equalize in the first half. Seattle entered the Leagues Cup break at fourth place in the Western Conference.
Leagues Cup club
C.F. Monterrey in their 2023 Leagues Cup group stage match on July 30. In July and August, MLS play halted for the
Leagues Cup, an international competition with
Liga MX clubs hosted in the United States and Canada. The Sounders were drawn into group West 2 alongside
Real Salt Lake and Liga MX's
Monterrey. They opened the tournament on the road with a loss to Real Salt Lake after a scoreless first half. The Sounders made several half-time substitutions and called for a penalty early, but instead conceded from a counter-attack while disputing the referee's non-call. Real Salt Lake defender
Marcelo Silva was shown a red card in the 60th minute for a foul, but the hosts won 3–0. The Sounders hosted Monterrey in the final matchday of the group stage and scored two goals in the first ten minutes, but then conceded four goals—including a
hat-trick by
Germán Berterame—to lose 4–2. The team were eliminated from the Leagues Cup and finished third in group West 2; their next match would be 20 days later in mid-August.
August and September The Sounders returned to regular season play on August 20 by hosting
Atlanta United FC at Lumen Field under hazy conditions due to
nearby wildfires. The team lost 2–0 as Atlanta's
Giorgos Giakoumakis scored in the 11th and 65th minutes to beat
Stefan Frei, who had been named captain and set a new club record for appearances in all competitions with his 340th match. The Sounders had several chances in the second half, but were unable to convert them. In their next match, on the road against
Minnesota United FC, the Sounders made several positional changes and earned a draw. Both goals in the 1–1 draw were created through headers by Yeimar—a 17th-minute goal for the Sounders and an
own goal in the second half—and Frei made three saves in the last minutes of the game. The team ended their six-match run without a win by defeating
Austin FC 2–1 during an away game at the end of August. The Sounders took the lead early in the second half through Jordan Morris while Frei made several saves to prevent Austin from scoring a second goal; both Morris's goal and a Frei save minutes later were reviewed by the video assistant referee but allowed to stand. The winning goal was scored at the beginning of stoppage time by Albert Rusnák after he received a rebound from an earlier shot by
Obed Vargas. The Sounders then hosted the Portland Timbers in their penultimate
Cascadia Cup fixture of the season; the home side took a 2–0 lead in the first half through goals by Raúl Ruidíaz and Léo Chú, who was sent off in the 53rd minute for his second yellow card of the match. The Timbers equalized through a pair of goals three minutes apart, but were held to a 2–2 draw after several saves from Frei. The two goals were the most the Sounders had scored at Lumen Field since April but extended a six-year home winless streak against the Timbers. The Sounders began a three-match road trip by playing
FC Dallas to a 1–1 draw that saw the return of Cristian Roldan following his concussion treatments. Dallas took the lead in the first half, but
Alex Roldán's volley off a cross by
Reed Baker-Whiting in the 57th minute tied the score. The team traveled to play the Colorado Rapids later in the week and won 2–1 to maintain their second-place rank in the Western Conference. Chú returned from his suspension to score the opening goal in the 34th minute, which was followed by Rusnák's header in the second half from a Cristian Roldan cross; the Rapids scored in the 80th minute, but were unable to find an equalizer and lost to the Sounders at home for the first time since 2018. After a one-week
bye, they finished the road trip with a scoreless draw against
Nashville SC. Héber's goal for the Sounders in the 58th minute was disallowed after video review due to an offside.
October The team clinched a playoff berth on October 4 with their 2–1 defeat of the
LA Galaxy, their first home win since July. The Sounders took the lead in the ninth minute through a header from Jordan Morris, but conceded an equalizer early in the second half; Cristian Roldan scored the winning goal in stoppage time off a throw-in by Alex Roldan that was headed towards him by
Josh Atencio. Seattle's final home regular season match was played three days later against Vancouver Whitecaps FC with 33,666 in attendance. It finished in a scoreless draw as Vancouver goalkeeper
Yohei Takaoka made five saves. The result dropped the Sounders to third in the Western Conference. On
Decision Day, the Sounders defeated conference leaders
St. Louis City SC 2–0 on the road and clinched second in the Western Conference; with a loss, the team could have finished as low as sixth. Both goals were scored in the first half, beginning with Rusnák's shot from distance in the 23rd minute, which was followed by Reed Baker-Whiting's attempt that was deflected by
Tim Parker as an own goal. Seattle finished the regular season with a 14–9–11 record and were undefeated in their final nine matches.
Stefan Frei set a team record for the most shutouts in a season at 14, surpassing his total in the
2017 season. The Sounders had an average attendance of 32,161 spectators per home match, the third highest in the league.
November: MLS Cup Playoffs As the second-place team in the Western Conference, the Sounders were paired with seventh-placed
FC Dallas in the first round of the playoffs, which would be played as a
best-of-three series. In the second game, the Sounders lost 3–1 after a penalty kick was awarded to Dallas by the video assistant referee in the 13th minute and a second goal five minutes later. Morris scored after half-time and had another goal that was ruled offside; a foul on Ruidíaz in the 75th minute was recommended for a potential penalty kick by the video assistant referee but was not awarded. A berth in the Conference Semifinals was clinched on November 10 with a 1–0 home victory, giving the Sounders a 2–1 result in the best-of-three series. Rusnák scored the lone goal of the match in the 36th minute amid several Seattle chances that missed or were saved by Dallas goalkeeper
Maarten Paes. The playoffs paused for three weeks due to an international break and resumed with the Conference Semifinals. The Sounders hosted defending MLS Cup champions Los Angeles FC in the Western Conference Semifinals on November 26 and lost 1–0 after they conceded a goal to
Denis Bouanga in the 30th minute. The Sounders had the majority of chances to score but failed to beat goalkeeper
Maxime Crépeau, who made seven saves. Referee
Ted Unkel was criticized by media and fans for his officiating during the match, particularly missed calls that would have been in Seattle's favor. The defeat marked the end of a 19-match unbeaten streak at home in the playoffs for the Sounders and was their first home playoff loss since 2013. ==Non-competitive matches==