GLENDALE, Ariz. -- Chicago Bears running back Matt Forte left Sunday's 28-13 victory over the Arizona Cardinals with a right ankle injury, but he said he will play in the regular season finale against the Detroit Lions next Sunday.

"Yeah, I'll play," said Forte, who was wearing a walking boot on his right foot as he left the locker room after the game.

That would be good news for a Bears team that must defeat the Lions and pull for the Green Bay Packers to beat the Minnesota Vikings to ensure Chicago's first playoff berth since 2010.

Forte appeared to injure the ankle on the Bears' opening drive of the second half. He immediately went to the sideline to have his right ankle re-taped and tried to test it out before being escorted back to the locker room.

Forte finished the game with 12 carries for 88 yards rushing yards and one touchdown. He also caught one pass for 7 yards.

He suffered a right ankle injury against the Packers in Week 2 that forced him to miss the next game, a victory over the Rams on Sept. 23. He also sprained his ankle a second time later in the season but did not miss any time.

"Not the worst I've ever felt but this is the third time so it's just aggravating," Forte said.

The loss of Forte left the Bears thin at running back after placing backup Michael Bush on injured reserve Tuesday with a rib injury. They re-signed Kahlil Bell Tuesday and have Armando Allen, who took over for Forte against the Cardinals. Bell rushed for 32 yards on 13 carries, and Allen ran for 24 yards on five attempts.

The Bears also lost starting safety Chris Conte with a hamstring injury late in the second quarter when he got tangled up with Arizona tight end Rob Housler on a short fade right in the corner of the end zone. The pass was ruled incomplete but Conte remained on the sideline for the Bears' final defensive series of the half and was later ruled out for the rest of the game.

Second-year player Anthony Walters replaced Conte at free safety.

The Bears lost reserve safety Craig Steltz two weeks ago when he tore a pectoral tendon that required surgery to repair. Steltz was placed on injured reserve on Dec. 11.

Conte started all 15 games for the Bears this year despite dislocating his shoulder in the preseason.

"Of course (Forte and Conte) are two valuable players for us, but it's always about the next guy stepping up," Bears coach Lovie Smith said. "Anthony Walters came in and did a pretty good job as did Armando Allen and Kahlil Bell with limited practice reps."

ESPNChicago.com Melissa Isaacson contributed to this report.