Philadelphia Eagles quarterback Michael Vick failed to pass a concussion test and will not be cleared to practice on Thursday.
Vick has not played since he suffered what coach Andy Reid called a "significant concussion" in a Week 10 game against the Dallas Cowboys.
The oft-injured quarterback had completed 58.5 percent of his passes for 2,165 yards with 11 touchdowns and nine interceptions this season.
He has played a full, 16-game season just once in his career, in 2006 for the Atlanta Falcons.
Rookie Nick Foles has started the last two games for Philadelphia in place of Vick and it seems likely he will make his third career start for the 3-8 Eagles.
Foles has completed 59.6 percent of his passes for 542 yards with a touchdown and three interceptions over two-plus games for Philadelphia, which is in the midst of a seven-game losing streak and will face the Cowboys on Sunday.