Dixon, who started the first two games of the season for the suspended Ben Roethlisberger, was examined by doctors Monday and might have additional tests Tuesday. Dixon, who injured the same knee at Oregon in 2007, might not return before Roethlisberger's four-game suspension ends.
Charlie Batch, No. 4 on the depth chart, finished up after Dixon was hurt Sunday during a 19-11 victory at Tennessee. He is currently the only healthy quarterback on the roster.
Byron Leftwich could start against Tampa Bay on Sunday, but he hasn't played since spraining his left knee during a Sept. 2 exhibition game.