As impressive as rookie right guard Kyle Long was in training camp and preseason, he struggled in the opener.
"Kyle was physical," said offensive coordinator Aaron Kromer. "There was a play or two where he didn't pick up the right guy in his pass protection or use the right technique in the running game, which a young guy has a tendency to do. You just have to keep working on it.
"You've just got to make sure it only happens once."
Kromer isn't too worried.
"The good thing about (Long) is, he knows exactly what he did wrong right afterward, and that's the sign of a guy who's going to improve," the coach said.
The Vikings signed J'Marcus Webb two days after he was cut by the Bears, and Minnesota coach Leslie Frazier has been questioning the lineman about his former team.
"I'm not finished," Frazier said. "We've got more questions for him."
Bears offensive coordinator Aaron Kromer isn't worried his unit will be compromised.
"There's more than one way to make our calls up front," Kromer said. "We don't feel any threat in that matter."
Frazier hopes the change of scenery will help Webb, who allowed 3 ½ sacks to Vikings DE Jared Allen in a 2011 finale.
"We're hoping he's going to be a solid backup tackle," Frazier said. "If we were to have a situation where he had to play, his experience should help him and help us."
Making the grade:
According to Pro Football Focus, rookie Jordan Mills had the highest grade of any Bears offensive linemen Sunday, and coach Marc Trestman has seen improvement in his play since training camp.
"His technique has improved dramatically," said Trestman. "He's certainly got the temperament to play the position. He's a calm guy. He's got the physical attributes.
"He's growing at a pretty fast pace."
DE Julius Peppers (flu-like symptoms) and corner Charles Tillman (knee/personal) were back at practice Friday after missing Thursday.
Tillman participated in full, while Peppers was limited. Both are probable for Sunday.
The Vikings list seven players as "probable," including four starters: DT Kevin Williams (knee), center John Sullivan (knee), CB Josh Robinson (quadriceps) and OT Phil Loadholt (knee).