CHARLOTTE, N.C. (AP) -- While he's not quite ready to name starters, Panthers coach Ron Rivera is pleased with how his offensive line has progressed following an offseason of change.
The Panthers lost four offensive linemen from last year's roster to retirement, including longtime left tackle Jordan Gross.
''That's a bummer,'' Rivera said following Wednesday's practice.
Despite the departures, most of Carolina's offensive linemen have some experience playing in the system with the exception of rookie Trai Turner, who has been working as the starting right guard.
''This line has done a nice job but it's not like we have replaced them with guys who haven't played for us,'' Rivera said.
Rivera said the offensive line is a still a work in progress, but ''for the most part it's shaping up very nicely and I like the direction we're headed. I feel confident and comfortable with this group.''
Rivera is particularly pleased with Byron Bell, last year's starting right tackle who's adjusting well to the move to left tackle where he'll be responsible for protecting quarterback Cam Newton's blindside.
Bell entered training camp in a battle with Nate Chandler.
But after flip-flopping Bell and Chandler at the two tackle spots early on at camp, Rivera appears to have settled on Bell as the starter. Bell has started both preseason games. Chandler has struggled to compete, missing the last week of practice with swelling in his knee.
''He's done a nice job, he really has,'' Rivera said of Bell, an undrafted rookie from New Mexico.
Bell did well Sunday night against Chiefs defensive end Tamba Hali, holding the four-time Pro Bowler at bay for the better part of the first half.
The left-handed Bell said left tackle is his more natural position. He played there at high school and most of college before moving to right tackle when he joined the Panthers in 2011.
''I'm getting a little rhythm now,'' Bell said.
He likes the idea of being settled in now at one position.
''It makes it a lot easier,'' Bell said. ''I don't have to change my stagger (step). I have can focus on one stagger. I can work on my footwork.''
It's still a very young line anchored by veteran center Ryan Kalil, who has represented the Panthers in three Pro Bowls.
Outside of Kalil, Bell is the only potential starter with significant playing experience having started 37 games in three seasons. Chandler, Turner and the other first-team guard Amini Silatolu have 11 combined starts.
''I think there is going to be some growing pains with this group more so than some of the older groups we have,'' Kalil said. ''But we have some really tremendous talent that I think will set us up for years to come.''
The Panthers will face the New England Patriots on Friday night in their third preseason game, marking the first time they've faced a 3-4 defense this preseason.
Rivera said the starters are expected to play 30 to 35 plays or roughly two quarters.
Garry Williams will start at right tackle for Chandler, who'll get another week to rest the knee. Chris Scott could see additional action at right guard with Turner missing some practice this week, too.
''This will be a real good test for our offensive line,'' Rivera said.
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