The Chicago Bears will stick with Mitchell Trubisky at quarterback for Sunday's game against the Philadelphia Eagles.

Chase Daniel is Trubisky's backup quarterback.

"Yes, there is [enough time left for Mitch to improve]," Matt Nagy said. "And we understand that we didn't get the win, but we felt there was definitely an improvement. We're going to make sure that we keep our noses to the grind, we stay positive, we stay really positive because that's who we are."

Khalil Mack will play the Oakland Raiders this Sunday for the first time he was traded to the Chicago Bears.

Mack expected to sign a long-term contract with the Raiders and spend his entire career with the franchise.

"That's the expectation when you get drafted to a team: You want to be there for the long haul and bring championships and all those good things," Mack said. "It's the business side of it that doesn't really let you do that."

Mack was drafted fifth overall by the Raiders in 2014.

Mack signed a lucrative multiyear deal with the Bears that included $90 million in total guarantees.

The Chicago Bears aren't saying why Roquan Smith was a healthy scratch on Sunday against the Minnesota Vikings.

"I'm just gonna say it was a personal issue," Matt Nagy said. "I'm not getting into anything else. I'm just gonna completely keep it at that."

When pressed about the issue, Nagy remained quiet.

"I'm not getting into anything with Roquan," the coach said.