Bears coach John Fox knows there is plenty of room for improvement against the New England Patriots in Thursday night’s second preseason game.

“Just the timing, the crispness of the tackling, the crispness of the blocking; all the things that you don’t do for six months that take some practice,” Fox said. “It perks up a little bit in those games, especially in the trenches, where your fight’s right in front of you. It takes a while to get that timing and conditioning back.”

That goes double for 2015 first-round draft pick Kevin White, who missed his entire rookie season after having shin surgery. The 6-foot-3 wide receiver has flashed in practice and had 1 catch for 3 yards in the preseason opener, but it’s a long road back.

“I think there’s some rust,” Fox said. “Anytime someone doesn’t practice and play (for a full year), we have to bring the WD-40 out and spray the rust off. (But) I’m seeing progress with him getting back into football condition.”

Doctor’s orders:

Tight end Zach Miller was not at Tuesday’s practice against the New England Patriots in Foxborough, but coach John Fox said his absence was due to a doctor’s appointment, as he goes through concussion protocol.

Miller was injured on July 31 but returned on a limited basis in three practices previous to Tuesday.

“We keep evaluating, keep looking and trying to make sure we cure all symptoms,” Fox said. “No setbacks, no new prognosis. When they’re ready to come out, they’ll come out.”

Linebacker Danny Trevathan was held out for rest. Cornerback Bryce Callahan was out with a muscle strain and is day to day. The Bears hope to have him ready for Thursday’s game.

No big deal:

Tuesday’s practice kerfuffle was more mild than the altercation between Bears wide receiver Alshon Jeffery and Patriots cornerback Malcolm Butler that got both players removed from the action.

“Those weren’t fights,” coach John Fox said. “Those were just pushing matches.”

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