Pictures of the Buccaneers' quarterbacks.
There really isn't much quarterback "depth" in the NFL. Plenty of teams roll with relatively unproven backups simply for lack of a better option. The Bucs had good depth the last two years by those standards, since young starter Jameis Winston was backed up by Mike Glennon, who had seen significant action the previous two seasons.
Glennon is now the Chicago Bears' starter, having picked up a lucrative free agency deal in the offseason, but the Bucs are still in decent shape behind Winston. Not only do they have Ryan Griffin, who they've been grooming for two years, but they also signed 13th-year passer Ryan Fitzpatrick to compete for the number-two job. Fitzpatrick has averaged nearly 13 starts over the past nine seasons and would surely prefer to remain one of the league's 32 first-teamers but he's the quintessential veteran safety net for the Buccaneers.
Tampa Bay's eventual depth at the position may boil down to just Winston and the winner of the Griffin-Fitzpatrick battle, with a third quarterback on the practice squad. The Bucs would prefer to carry only two passers and free up another roster spot, but it is possible they will roll with three QBs for the third straight year. All things considered, the Bucs have set themselves up for the potential of a Winston absence about as well as they could, but depth at the quarterback position will almost always be thin on an NFL roster.