CHICAGO -- The Chicago Bears made a handful of roster moves on Saturday when they elevated running back Armando Allen to the active roster from the practice squad, placed vested veteran running back Lorenzo Booker on injured reserve and waived linebacker Patrick Trahan.

Booker originally made the Bears' 53-man roster as the No. 3 running back but sustained a head injury in the club's final preseason game at Cleveland. He did not practice the entire week leading up to the regular-season opener against the Indianapolis Colts. He was listed as questionable on the official injury report released on Friday.

Allen had filled in for Booker on special teams this week in practice in anticipation of the move.

Allen spent 12 weeks on the Bears' practice squad last season before being elevated to the active roster for the final two games of the regular season. During those contests, he carried the ball 15 times for 48 yards.

Trahan made the squad out of the preseason as the seventh linebacker after he appeared in five games for the Bears last year and recorded five special teams tackles. He spent the first 12 weeks of the 2011 season on the Bears practice squad.

The Bears' roster now stands at 52 players but defensive tackle Nate Collins is on the reserve/suspended list for Week 1 and will count against the team's roster starting next week.