Gruber spent his entire National Football League career with the Tampa Bay Buccaneers from 1988 to 1999. He never missed a snap in his first five years in the league. Over his 12-year career he appeared in 183 games, starting all of them, which was a Buccaneers record until Derrick Brooks broke it in 2007.
For most of his career, Gruber was one of the few marquee players on a bad team; indeed, his early years were spent on some of the worst teams in Bucs history. He missed the last part of the 1999 season, in which the Buccaneers advanced all the way to the NFC Championship Game, due to a broken leg. The injury was slow to heal in the offseason, which was a factor in his decision to retire during the summer of 2000.
On June 6, 2012, it was announced that Paul Gruber will be the latest member of the Tampa Bay Buccaneer Ring of Honor. Gruber will join hall of famer Lee Roy Selmon, former coach John McKay and tight end Jimmie Giles as the fourth inductee into the Ring of Honor, established in 2009.