Titans quarterback Jake Locker will miss the rest of the season with a Lisfranc injury to his right foot that may need surgery.
Coach Mike Munchak said Monday losing Locker now is a huge blow for the Titans (4-5).
The quarterback was hurt in the second quarter of a 29-27 loss to Jacksonville at the end of an option play.
Locker needed crutches and a walking boot to leave the stadium. Locker is 8-10 since becoming a starter, but will wind up missing 14 of a possible 32 starts in his first two seasons.
Munchak says they don't know yet if Locker will need surgery.
Ryan Fitzpatrick replaces Locker with the Titans hosting Indianapolis on Thursday night.
AP NFL website: www.pro32.ap.org