Posted by ESPN.com's Mike Sando
As John Clayton notes, 11 teams have started backup quarterbacks this season and two teams -- including the Seahawks -- have started third-string players at the position. The Chiefs are the other team to start a No. 3 quarterback.
One question at this point is whether the 49ers are essentially starting a third-stringer as well, albeit by choice. Alex Smith and Shaun Hill were the top two quarterbacks through the early stages of training camp. Third-stringer J.T. O'Sullivan eventually emerged with the job.
The chart shows two sides of O'Sullivan through the first seven games. We have seen the O'Sullivan who was setting an improbable pace through three games. And we have seen the O'Sullivan who was no match for the Giants while continuing his increasingly turnover-prone ways.