He then played for three seasons at the University of North Dakota and on the US national team at the 2004 and 2005 World Junior Ice Hockey Championships.

With nine points in the first 11 games of the season, he caught the attention of Sabres management, and was called up to Buffalo in early November to replace injured winger Maxim Afinogenov.

Stafford became a regular in the Sabres' lineup during the 2007–08 season, scoring his first career hat-trick against the Atlanta Thrashers on January 18, 2008.

[3] In his ninth season with the Sabres in 2014–15, on February 11, 2015, Stafford was traded alongside Tyler Myers, Brendan Lemieux, Joel Armia and a 2015 first-round draft pick (Jack Roslovic) to the Winnipeg Jets in exchange for Evander Kane, Zach Bogosian and the rights to goaltending prospect Jason Kasdorf.

[7] On March 1, 2017, Stafford was traded from Winnipeg to the Boston Bruins for a conditional 6th round pick in the 2018 NHL Entry Draft.

[14][non-primary source needed] On January 4, 2019, Stafford scored the game-winning shootout goal in his 800th regular season NHL game.

[17] Stafford formed a band called Red Seal Peach while at the University of North Dakota with goaltender Jordan Parise.

[18] Stafford appears in the Every Time I Die video for "Decayin with the Boys," playing jenga at a party in full hockey uniform.