By Chris Emma–

LAKE FOREST, Ill. (CBS) — The Bears gave added responsibility to rookie quarterback Mitchell Trubisky on Wednesday, giving him reps with the first-team offense in practice.

Coach John Fox confirmed that the team is moving forward with veteran quarterback Mike Glennon as the starter and Mark Sanchez as the backup, explaining that Trubisky’s work is for evaluational purposes with the first-team offense.

“I was excited, but it shouldn’t make a difference how I approach things,” Trubisky said of the change. “You always prepare like you’re the starter and always support your teammates. Whatever group you’re in, you just continue to make them better and get yourself better. Yeah, it’s all about reps like I’ve been saying. The more I can get, the better I should have a feel for things. Whatever group I’m with, just go out there, lead and show them what I can do.

“I’m just focused on what I can control: my effort, my attitude. Come out here, practice hard, get better every day and in due time, you’ve got to earn a spot. Every spot is earned. That’s what we’re trying to do, just create competition on both sides of the ball to make this team better.”

It was the first time Trubisky worked with the starters and came four days before the Bears face the Titans in their third preseason game Sunday. Glennon will work the first half of Sunday’s game and Trubisky will take over to start the second half. Fox hopes that the Titans will counter Trubisky with their first-team defense.

Fox refused to say whether the Bears have opened a quarterback battle. Glennon is now entering familiar territory after losing his place as the Buccaneers’ starter in 2014 to Jameis Winston, the No. 1 overall pick.

“I mean, déjà vu,” Glennon said. “Again, it’s situations that I’ve been through before that I handled myself well in the past, and I’ll continue to do that in his situation.

“Really to control what you can control. Outside of that, it just doesn’t do you any good to worry about other things. Just any of that. All I can do is prepare for Tennessee and treat it just like anything else.”

Chris Emma covers the Bears, Chicago’s sports scene and more for Follow him on Twitter @CEmma670 and like his Facebook page.

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