FLOWERY BRANCH, Ga. (AP) - It's no secret that the new starters on Atlanta's offensive line, especially right tackle Lamar Holmes, will get a lot of attention from the Saints in Sunday's opening game.

The new-look line must adjust to the departures of center Todd McClure, who retired, and right tackle Tyson Clabo, who was not re-signed. Holmes, who has played in only one game, was rushed into the starting unit when Mike Johnson dislocated his left ankle and broke his left leg this summer.

The Falcons have only two linemen in the same starting positions as last season, and that's the sort of development that doesn't slip past opposing teams.

Of course we noticed that,'' said New Orleans outside linebacker Junior Galette.It's on film. ... Obviously they let Clabo go. That right side of the line, we want to do our best to take advantage of that line that we can, but who's to say the next man up is not better than the guys that were out there before?

``We haven't really seen so much of them. We've got to test it out, basically.''

Peter Konz, a part-time starter at right guard last season, has moved to center. The only starters at the same spots as last year are left tackle Sam Baker and left guard Justin Blalock.

Holmes and Konz were 2012 draft picks.

Blalock, beginning his seventh season, suddenly has the most tenure of the unit.

It was a quick transition,'' Blalock said with a smile following Friday's practice.I went from being in the middle of the pack to the old guy.''

Blalock and Baker must provide stability on the left side of the line while the other starters gain confidence.

At stake is the success of an offense stacked with big-play talent. The health of quarterback Matt Ryan, who signed a contract extension worth nearly $104 million at the start of training camp, also is riding on the play of the line.

Ryan was sacked five times by Tennessee in the third week of the preseason, the game regarded as the dress rehearsal for the regular season. The Falcons were 0-4 in the preseason.

Obviously, we've got some younger guys coming in to play for us with two veterans being gone,'' Ryan said Wednesday.But the guys have done a great job in camp. There's been some ups, been some downs. We've got a lot to learn from. But I expect the guys to go out there and play really well for us on Sunday.''

Blalock said the makeover of the line ``has gone pretty well so far.''

Obviously there have been some growing pains, and that's to be expected when you have turnover in your group,'' Blalock said.There's a lot to be optimistic about with some things we have been able to do.''

The Falcons signed veteran tackle Jeremy Trueblood this week. Trueblood joins undrafted rookie Ryan Schraeder as the backups at tackle. Joe Hawley is the top reserve at the interior line spots.

The move by Konz from guard to center was expected when he was drafted in the second round from Wisconsin. Konz was regarded as a center in the 2012 draft and he practiced at guard and center as a rookie.

I think he's done extremely well,'' Blalock said of Konz.Obviously, it's a position he's familiar with, playing it in college. I'm not saying it's an easy transition but even last year in practice he worked a lot there as well.''

Konz said he's glad he won't be playing his first game in the Superdome.

Since training camp I have felt very comfortable,'' Konz said.The communication has been good. The transition has been good and then going out and working hard has given me a lot of confidence.

``As far as this Sunday, having played there before and playing the Saints twice gives me a lot of confidence because I know how the Dome is going to be. It's not going to be totally new for me.''

The spotlight will be on Holmes, whose progress was slowed last year when he missed training camp with a foot injury.

The good news for Atlanta is Johnson's injury came early in camp. Holmes has had a full month with the first-team line.

``You never want somebody to go down, but when somebody steps in, it was fortunate for Lamar to get as many reps as he has with the first team,'' Konz said.

NOTES: WR Roddy White (sprained left ankle), linebacker Stephen Nicholas (thigh) and cornerback Asante Samuel (right thigh) were listed as questionable on the Friday injury report. Each had limited participation in Friday's light practice. White promised on Thursday that he will play.

AP Sports Writer Brett Martel in New Orleans contributed to this report.

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