Youth Reaves began playing hockey at age five and football at age eight. As a youth, Reaves played in the 2000
Quebec International Pee-Wee Hockey Tournament with the Winnipeg South Monarchs
minor ice hockey team. Although he played both football and hockey growing up, after tearing his posterior cruciate ligament during a hockey tournament, he was forced to forfeit football as a sport. Reaves was eventually drafted 36th overall by the
Brandon Wheat Kings in the 2002 WHL bantam draft. Despite his draft selection, Reaves continued to play for the
St. John's-Ravenscourt School hockey team where he led them to the 2004 McDonald's Provincial High School Hockey Championship. Reaves joined the Wheat Kings for his rookie campaign during the
2004–05 season. Prior to the
2005–06 season, Reaves was named an alternate captain alongside
Mark Derlago,
Riley Day, and
Derek LeBlanc.
Professional St. Louis Blues in March 2014. Reaves was drafted by the
St. Louis Blues 156th overall in the
2005 NHL entry draft. On May 15, 2007, Reaves signed a three-year entry-level contract with the St. Louis Blues. At the conclusion of his major junior season, Reaves attended the Blues 2007 training camp and was reassigned to their
American Hockey League affiliate, the
Peoria Rivermen. While playing with the Rivermen during the
2007–08 season, he suffered an injury in a game against the
Rockford IceHogs and was reassigned to the Blues
ECHL affiliate, the
Alaska Aces. Reaves was recalled from the Peoria Rivermen by the Blues on October 10, 2010, after
Cam Janssen suffered a concussion from a hit to the head in the Blues season opener on October 9. Reaves made his NHL debut on October 11, 2010, where he served 15 penalty minutes in the Blues' 5–1 win over the
Anaheim Ducks. He was returned to Peoria after two games with the Blues as
Vladimír Sobotka returned from the
Injured reserve list. He later scored his first NHL goal on January 12, 2011, again against the Ducks, on goaltender
Jonas Hiller. Reaves' 2015–16 season was cut short due to a knee injury and he returned to the Blues' lineup weighing 225 instead of his usual 230. During the offseason, he trained with Blues assistant coach/video coach Sean Ferrell.
Pittsburgh Penguins On June 23, 2017, after seven seasons with the Blues, Reaves was traded to the
Pittsburgh Penguins along with a second-round pick (51st overall) in the
2017 NHL entry draft in exchange for
Oskar Sundqvist and the Penguins' first-round pick (31st overall) in the 2017 draft. In the
2017–18 season, Reaves added muscle to the Penguins lower lines, providing 4 goals and 8 points in 58 games.
Vegas Golden Knights On February 23, 2018, Reaves was involved in a trade with the
Vegas Golden Knights. The Penguins received
Tobias Lindberg from the Golden Knights in exchange for Reaves as part of a three-way trade also involving the
Ottawa Senators. Reaves scored the series-winning goal over the
Winnipeg Jets that qualified the Golden Knights for the
2018 Stanley Cup Final. He also scored in game 1 of the Stanley Cup Final in a 6–4 Golden Knights victory, though the
Washington Capitals would come back and win the next four games for the Stanley Cup. On July 1, 2018, Reaves signed a two-year contract with the Golden Knights. He recorded a career-high nine goals and 20 points the
subsequent season. On June 15, 2020, the Golden Knights signed Reaves to a two-year, $3.5 million contract extension. On May 31, 2021, Reaves was suspended for five games in the second round of the
2021 Stanley Cup playoffs for an injury on
Colorado Avalanche skater
Ryan Graves.
New York Rangers in December 2021 On July 29, 2021, the Golden Knights traded Reaves to the
New York Rangers for a
2022 third-round draft pick, and on July 31, he signed a one-year contract extension with the team.
Minnesota Wild After going scoreless in 12 games with the Rangers to open the
2022–23 season, Reaves was traded by New York to the
Minnesota Wild in exchange for a fifth-round pick in the 2025 NHL Entry Draft on November 23, 2022.
Toronto Maple Leafs After opting to hear offers on the free agent market, Reaves signed a three-year, $4.05 million contract with the
Toronto Maple Leafs on July 1, 2023.
San Jose Sharks On July 10, 2025, Reaves was traded to the
San Jose Sharks in exchange for
Henry Thrun. ==Playing style==