He resumed play with a planned three-game conditioning assignment to the American Hockey League Worcester Sharks on January 16, 2009, but he suffered another injury to the same leg during play on January 18. He missed the remainder of the regular season, later making his season debut in the Sharks third playoff game. After a 2008–09 season marred by injury, Mitchell became a restricted free agent in the off-season, eventually re-signing with the Sharks on a three-year, $4.1 million contract. Minnesota Wild On July 1, 2012, Mitchell signed as a free agent to a three-year contract with the Minnesota Wild. Due to the 2012–13 NHL lockout, however, Mitchell signed a standard contract with the San Francisco Bulls of the ECHL on December 31, 2012. He played his first official game as a Bull two days later and scored the only regulation goal for the team at their home arena, the Cow Palace, in a 2–1 shootout loss. Buffalo Sabres On March 5, 2014, Mitchell was traded to the Buffalo Sabres, along with a second-round draft pick in 2014 and a second-round pick in 2016 (traded to Montreal for Josh Gorges), in exchange for Matt Moulson and Cody McCormick. Mitchell finished the season with 2 goals and 10 points in 67 games. Montreal Canadiens In the following 2014–15 season, Mitchell was again moved at the NHL trade deadline – he was shipped to the Montreal Canadiens in exchange for Jack Nevins and a seventh-round draft pick in 2016 on March 2, 2015. On June 15, 2015, Mitchell signed a three-year contract to remain with the Canadiens for a reported $3.6 million. Los Angeles Kings During the 2017–18 season, having played in 11 scoreless games in his fourth year within the Canadiens, Mitchell was traded to the Los Angeles Kings in exchange for a conditional fifth-round pick on November 23, 2017. In assuming a checking-line role with the Kings, Mitchell appeared in 49 games, registering 6 goals and 11 points. Lausanne HC As a free agent from the Kings, Mitchell opted to embark on a career abroad, agreeing to a one-year contract in Switzerland, worth CHF 700,000 with Lausanne HC of the National League (NL) on July 17, 2018. After only appearing in 28 regular season games (12 points) with Lausanne in 2018/19 and playing for Team Canada in the 2018 Spengler Cup, Mitchell's season came to an abrupt end suffering a