Early career Geekie was selected by the
Tri-City Americans of the
Western Hockey League (WHL) in the fifth round, 90th overall, of the 2013
WHL bantam draft. For the 2013–14 season, Geekie remained in his native Manitoba, playing
minor hockey with the Yellowhead Chiefs of the
Manitoba U-18 'AAA' Hockey League (MMHL). In his rookie season with the Chiefs, Geekie led the Chiefs with 25
goals and 53
points through 44 games, also placing 12th in league scoring. On March 14, 2014, Geekie signed a contract with Americans. He subsequently joined the Americans for their final regular-season game, in which he scored the team's only goal in an eventual 6–1 loss. Geekie played two games with the
Neepawa Titans of the
Manitoba Junior Hockey League and nine games with the Americans before returning to the Chiefs. Geekie recorded one goal and one
assist with the Titans and two assists with the Americans. On December 29, 2014, partway through the season with the Chiefs, Geekie was named to the MMHL's First All-Star Team after he tallied 16 goals and 42 points in 26 games, placing second in the league in scoring at the time. Geekie finished the season with the Chiefs notching 27 goals and 36 assists through 44 games.
Major junior Geekie began his first full
major junior campaign with the Americans during the
2015–16 season, in which he scored 12 goals and 25 points through 66 games. Due to his performance, he was named to the WHL's Western Conference Second All-Star Team. He was subsequently ranked 42nd amongst North American skaters by the
NHL Central Scouting Bureau, before the
2017 NHL entry draft. On June 24, 2017, he was one of two players taken by the
Carolina Hurricanes in the third round, 67th overall, at the draft. Following his selection, he participated in the Hurricanes' development camp in the summer of 2017. In September, he was returned to the Americans from the camp. During the
2017–18 season, his final junior hockey campaign, Geekie tallied 30 goals and 54 assists through 68 games in the regular season. Through 14 playoff games, Geekie led the WHL with 17 goals, and he also collected 10 assists for 27 points. The Americans were eliminated from the playoffs in the third round of the playoffs by the
Everett Silvertips.
Professional Carolina Hurricanes Following the Americans' elimination from the playoffs, Geekie signed an
amateur tryout offer with the Hurricanes'
American Hockey League (AHL) affiliate, the
Charlotte Checkers, for the remainder of their regular season on May 4, 2018. Six days later, Geekie signed a three-year,
entry-level contract with the Carolina Hurricanes. he was re-assigned to the Checkers for the
2018–19 season. In 73 games throughout the regular season, Geekie tallied 19 goals and 27 assists. During the
2019 Calder Cup playoffs, he set the Checkers' postseason point streak record, putting up numbers in eight straight games. The Checkers defeated the
Chicago Wolves in five games to clinch the
Calder Cup, and Geekie totaled eight goals at 18 points through 19 playoff contests. Geekie joined the Checkers again to start the
2019–20 season. On March 7, 2020, he was called up to the Hurricanes after he put up 20 goals and 22 assists through 55 games with the Checkers. On March 10, against the
Detroit Red Wings, Geekie scored his third goal on only the fourth shot of his NHL career. After playing nine games with the Hurricanes, he was sent down to the team's new AHL affiliate, the
Chicago Wolves, on February 18, 2021. In only two games with the Wolves, he notched four goals and one assist, causing him to be named AHL Player of the Week. On February 22, he was recalled to the Hurricanes. On March 12, he scored two goals as part of a 5–1 victory over the
Nashville Predators. Geekie finished the season with the Hurricanes achieving three goals and six assists through 36 games. During the
2021 Calder Cup playoffs, he played in three games. On July 16, 2021, he signed a one-year, entry-level contract extension to remain with the Hurricanes.
Seattle Kraken Despite re-signing with the Hurricanes, Geekie was selected from the Hurricanes at the
2021 NHL expansion draft by the
Seattle Kraken on July 21, 2021. He was named to the team's inaugural opening roster before the
2021–22 season. He scored his first goal with the team in their first game, on October 12, the third Kraken goal in a 4–3 loss to the
Vegas Golden Knights. In 73 games during the season, Geekie totaled seven goals and 15 assists. As a
restricted free agent in the offseason, Geekie filed for arbitration before settling to a one-year, contract extension with the Kraken on July 24, 2022. During the
2022–23 season, starting on January 28, 2023, Geekie was scoreless for 10 straight games before breaking his drought by scoring two goals in a 5–3 victory over the
St. Louis Blues on March 1. By the end of the season, Geekie's career-high numbers increased, after he tallied nine goals and 19 assists for 28 points in 69 games, while maintaining a
+14 rating. In 13 games of the
2023 Stanley Cup playoffs, he managed two goals and two assists. On July 1, 2023, the opening day of free agency, he signed a two-year, contract with the
Boston Bruins. On February 29, 2024, he recorded the first NHL
hat-trick of his career as part of a 5–4 victory against the Vegas Golden Knights. Through 76 games of the
2023–24 season, Geekie totaled 17 goals and 22 assists for 39 points, all career highs. During the
2024 Stanley Cup playoffs, he achieved four goals and one assist in 13 games. In his first game back, Geekie was placed on a line with
David Pastrnak and scored his first goal of the season. After that game, Geekie became a regular fixture on the Bruins' top line and by December, had returned to form, scoring goals more consistently. By February 22, 2025, Geekie had scored his 18th goal of the season, surpassing his career high. On April 5, against the Carolina Hurricanes, Geekie notched a goal and four assists in a 5–1 victory, factoring in on all Bruins goals. He hit the 30-goal mark for the first time in his career three days later against the
New Jersey Devils. Geekie became the first Bruins player other than Pastrnak, Brad Marchand, or
Patrice Bergeron to score 30 goals in a season since
Loui Eriksson during
2015–16. Geekie finished the season with a career-high 33 goals and 24 assists for 57 points. Geekie hoped to build off his career year in
2025–26 season, and he started off hot, scoring nine goals in the first month of the season, including a five-game goal streak at the end of October. He continued to produce and show his prowess as a goalscorer alongside David Pastrnak, scoring eight goals in six games at the end of November. On March 5, 2026, Geekie scored his 34th goal of the season, passing his career high the previous season. However, afterwards, Geekie got snakebitten, and didn't score a goal for 17 straight games. On April 7, Geekie got back on the scoresheet against the
Carolina Hurricanes, and for good measure, scored two more to register his first
hat-trick of the season and the second of his career. == International play ==