ORCHARD PARK, N.Y. (AP) — Buffalo Bills quarterback Josh Allen remains in the NFL’s concussion protocol, opening the possibility of backup Matt Barkley starting Sunday against the Tennessee Titans.

Coach Sean McDermott says Allen will be limited to attending team meetings and individual drill work during practice Wednesday.

Allen was hurt following a helmet-to-helmet hit by Jonathan Jones in the fourth quarter of Buffalo’s 16-10 loss to New England last weekend.

Barkley finished 9 of 16 for 127 yards and a game-sealing interception that ended Buffalo’s final drive.

The seventh-year journeyman signed with Buffalo last Oct. 30 and started less than two weeks later with Allen sidelined with a strained right throwing elbow. Barkley went 15 of 25 for 232 yards and two touchdowns in a 41-10 victory at the New York Jets.

The outing led to Buffalo signing Barkley to a two-year contract extension.