With Henry Melton sidelined because of a concussion, Nate Collins received more snaps Thursday night against the Chargers as he did in the preseason opener at Carolina -- when he tied for the team lead with 4 tackles and had the Bears' only sack.
"He was active in the (first) game," said Bears defensive coordinator Mel Tucker, who coached Collins for two years (2010-11) as the Jaguars' defensive coordinator. "He's done a good job out here. He's gotten better. I was very fortunate to have Nate in Jacksonville, so I know him. I've seen the progress that he's made and he has improved as a player.
"We're still seeing what the roles are going to be. They'll be defined at some point. And then there's nothing ever set in stone. But so far he's shown that he's a guy that can help us. He can be active inside. He's tough in the run game, he's active against the pass and he continues to work hard. He's not a guy that will sit back and rest. He's really a go-getter out there."
Collins had another sack in the first quarter against the Chargers, bursting up the middle to nail Philip Rivers and take San Diego out of field-goal range. He made 3 first-half tackles, tied with linebacker James Anderson and defensive end Corey Wootton, 1 behind defensive end Shea McClellin's 4.
Earlier in the week Bears coach Marc Trestman wouldn't commit to starting rookie offensive linemen Kyle Long or Jordan Mills, even though they lined up with the ones the entire week in practice. The coach said only that they would get plenty of playing time, and he was right.
"They're going to get significant work again, and they'll have the opportunity to play some against San Diego's ones," Trestman said.
Both played a team-high 51 snaps in the preseason opener, and both were in the starting lineup Thursday night. Right tackle Mills, a fifth-round pick, and right guard Long, a first-rounder, helped pave the way for Matt Forte's 3-yard TD run over the right side late in the first quarter.
Both rookies stayed in at the start of the second quarter to play with the second-team offense.
"Kyle and Jordan are doing a (heck) of a job of going in there and stepping up and going against the ones and making that transition," veteran center Roberto Garza said after the rookies practiced all week with the first team. "Obviously it's an evolving process, but those kids are both very talented and have a bright future ahead."
Rookie Jonathan Bostic started his second straight game at middle linebacker with veteran D.J. Williams still out with a calf injury.
"I like his progress," defensive coordinator Mel Tucker said before the game of the second-round pick from Florida. "I think he's gaining confidence in what he's being asked to do from technique and assignment standpoints, like any new player in a system. But he has a very good demeanor; it's not too big for him. He's physical, and if he continues to keep his head down, work hard, keep his mouth shut and do what we ask him to do, he'll gain the respect of his teammates more and more every day."
Bostic and defensive end Shea McClellin dropped Chargers' running back Ryan Matthews for a 1-yard loss in the first quarter.
Tight (end) contest:
Martellus Bennett will be the Bears' only every-down tight end, but several players are scrambling to carve out a relevant niche behind him on the depth chart.
"Obviously, we'd like to have a guy who can block and run," offensive coordinator Aaron Kromer said. "You want to get the guy who can block and catch a pass; you don't wan to get one-sided. But, if a guy is that much better of a blocker than the other guy is a pass receiver, than you keep the blocker."
Five players -- Steve Maneri, Kyle Adams, Gabe Miller, Leonard Pope and Fendi Onobun -- are competing for two or three backup spots.
Sitting it out:
Defensive end Julius Peppers (coach's decision), wide receiver Earl Bennett (concussion), offensive tackle Jonathan Scott (right knee), defensive tackle Henry Melton (concussion), long-snapper Patrick Mannelly (ribs), linebacker D.J. Williams (calf) and running back Armando Allen (hamstring) did not play against the Chargers.
Third-string quarterback Matt Blanchard suffered a broken knuckle on his left hand in the third quarter. There is no timetable for his return.