Leno, Massie only constants with Chicago Bears' O-line

Bobby Massie, who cames to the Bears as an unrestricted free agent, started 15 games for Chicago last season. Associated Press

Bears left tackle Charles Leno has started 29 straight games, beginning in early 2015, the year after he was drafted in the seventh round out of Boise State. Associated Press

The only constants on the Chicago Bears' offensive line since they reported for training camp a month ago have been left tackle Charles Leno and right tackle Bobby Massie.

In between those two is some uncertainty.

Left guard Kyle Long is still battling back from last season's ankle surgery and has not even been cleared to practice without restrictions.

Right guard Josh Sitton has flip-flopped positions with Long, and he missed the first week of camp on paternity leave.

Cody Whitehair, an impressive 16-game starter at center last year as a rookie, worked at left guard with the first team in Saturday's second preseason game. That's a precaution in the event Long isn't ready to start the regular-season opener on Sept. 10 against Atlanta.

Hroniss Grasu, who missed last season after suffering a torn ACL in training camp, moved back into the No. 1 center job, where he was scheduled to start before his knee injury.

But the Bears' bookends at tackle have been reliable.

Leno has started 29 straight games, beginning in early 2015, the year after he was drafted in the seventh round (246th overall) out of Boise State.

Massie started 15 games for the Bears last year after he was signed as an unrestricted free agent. He started 46 games in four years with the Arizona Cardinals after they drafted him in the fourth round (112th overall) in 2012.

But the sooner the Bears get back to full strength on the inside of the line -- or at least decide on a starting five -- the better chance they have of improving on last year's offense that outscored just three of 32 teams.

Continuity along the O-line is imperative because it functions as a group, and each man must know what the players next to him are doing.

"It's a unit," Massie said. "It's not running back or a quarterback. It's not a position that can depend on (only) one player -- it's all of us together. If all five guys are not working together, then it's going to be a (shabby) show."

Traditionally, offensive linemen maintain their strong bond on the field, in the locker room and off the field.

"There's 11 players on the field, and we have five of those guys, so you have to have a good rapport," Leno said. "That's why you try to build a good team bond inside the locker room, especially with the O-line, because you never know when a guy might go down and you might have to step up."

The O-line's second-game performance was significantly improved, according to coach John Fox.

"Our offensive line, especially the first group, was a lot more efficient," Fox said. "I think our run game showed that. I think protection-wise showed that."

Even without No. 1 running back Jordan Howard, who stayed home with a scratched cornea, the ground game was effective. The first unit, which played only the first half, produced 76 rushing yards on 16 carries for a 4.8-yard average.

A healthy return of Long would provide a boost, but the three-time Pro Bowl pick needs a lot of full-speed reps before he fits smoothly into the operation.

"It's going to be tough on him, but he's a professional," Leno said. "That's what he gets paid to do. He has to make sure that he's prepared to come out and work whenever he's ready. That's just on him; that's his timeline.

"We've been out here doing it, so he's got to play this (catch-up) game. He has to step up and adjust to everything that we're doing already."

Long had been champing at the bit to get back, but the Bears are taking a cautious approach. Massie is confident Long will get back to his old form, but he knows it won't happen overnight.

"It'll take him a while to knock off the rust off, just like anybody who hasn't put on pads since January. I don't think it'll be a hard transition, and when he comes back, it's going to roll just like he was never gone. It won't be anything different.

"I know it's rough for him, and he's had some adversity, but who hasn't?"

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