BOURBONNAIS -- Despite adding talent and depth at a position that perennially has been a sore spot, the Bears still enter Friday night's preseason opener with a lot of unanswered questions regarding their rebuilt offensive line.
The key addition, two-time Pro Bowl left tackle Jermon Bushrod, is unlikely to play because he's still not back to full speed after missing a week with a calf injury.
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Eben Britton has taken the majority of the snaps at left tackle in Bushrod's absence, and he's expected to start on the road against the Carolina Panthers (7 p.m., Fox 32, WBBM 780-AM), with Matt Slauson at left guard, Roberto Garza at center, James Brown at right guard and J'Marcus Webb at right tackle.
It would be an upset if first-round draft pick Kyle Long doesn't win the right-guard spot by the regular-season opener, and there could be other changes as well.
Coach Marc Trestman and offensive coordinator/offensive line coach Aaron Kromer still are in the process of evaluating and deciding on their top five linemen.
Britton, who won't start at left tackle during the season if Bushrod is healthy, has versatility and still could win a starting spot elsewhere on the line. He and others could improve their status with impressive preseason performances.
"Eben is in the mix of finding where our offensive line will be," Trestman said. "He's had a very productive camp. He's versatile; he can play just about anywhere we put him, both on the left and right side.
"At this point, I can say he's definitely involved in being part of this roster on a week-to-week basis, (one of) the 46 (who dress on game day)."
Tackle Jonathan Scott's finicky right knee further clouds the O-line picture. He won't play against Carolina and hasn't practiced for more than a week, but he still could challenge Webb at right tackle, and he took some snaps at left tackle immediately after Bushrod was injured.
"We certainly would like him back, but he's day to day," Trestman said of Scott. "The next man up is really where we're at. And it's given an opportunity to guys like Eben, getting more looks at (rookie) Jordan Mills, getting a better look at J'Marcus Webb, and trying to build our offensive line."
Backup quarterbacks Josh McCown and Matt Blanchard will get long looks in the opener behind the rejiggered line. McCown threw more preseason passes last year than any Bears quarterback and posted a solid 82.3 passer rating.
Although McCown has started just two regular-season games in the previous five years (both with the Bears in 2011) and thrown just 61 passes since the start of the 2008 season, Trestman considers him a solid backup to Jay Cutler.
"I'm very confident," the coach said. "He's got a high skill set. He's very important to our locker room in a lot of different ways, as a complete player. He knows this offense in terms of where we are right now.
"He's where we thought we wouldn't be at this point -- we're a little bit ahead in our development, at least the understanding of what we're trying to accomplish.
"He's throwing the ball very effectively. We keep stats on everything we're doing, and for the most part he's been very efficient."
Blanchard, the third-team quarterback, played sparingly in the 2012 preseason and spent most of the regular season on the practice squad. The former Lake Zurich High School star has done a commendable job of avoiding mistakes and turnovers while getting more practice time than many teams give a No. 3 QB.
"He's going to play in a different environment," Trestman said of Blanchard in Friday night's game. "He's going to play for us in the last part of the third quarter and the fourth quarter.
"He's going to be heavily involved in managing the game, which is not easy to do in those times. It can get a little chaotic. We want to see him keep his poise, be efficient and take his time with the football.
"The first one's the most important. The team will trust him and the coaches will trust him if he can go out there and take care of the football during the time he's in. His productivity isn't as important as his ability to play smart and do the right thing with the ball."
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