FLOWERY BRANCH, Ga. -- Atlanta Falcons offensive coordinator Dirk Koetter has plenty of respect for how the offensive line has held up as of late.

The Falcons, of course, lost three linemen who had started a game this season to season-ending injuries: Joe Hawley, Lamar Holmes, and Peter Konz. They also lost projected starting left tackle Sam Baker (knee) and reserve Mike Johnson (foot) in the preseason.

Now, the Falcons will take an offensive line that includes two undrafted players and a rookie first-round pick coming off a serious ankle injury into battle against Carolina, a team that sacked Matt Ryan nine times and hit him 14 times in last year's season-finale at the Georgia Dome.

"You use the terms 'come together.' Come together takes a long time, especially in the O-line," Koetter said. "You've got guards and centers and tackles that play together for years. So the number of combinations we've had to put out there with our O-line, (it's) well-documented that we're on our third center, we're on our fourth right tackle.

"What James Stone and Ryan Schraeder are doing with the cards they were dealt, shoot, those guys are doing a heck of a job. Justin Blalock is the veteran in there now; Jon Asamoah, the free-agent we signed. Jake (Matthews) is in his rookie year; moved him from right to left. Every week is a new experience to Jake because every guy he plays against, he's playing against that guy for the first time."

In last Sunday's 27-17 win over Tampa Bay, the line kept Ryan clean, for the most part, and kept Buccaneers defensive tackle Gerald McCoy quiet. The run blocking was solid as well, thanks to some added help from Gabe Carimi and tight end Levine Toilolo.

Not flawless, but solid.

"It's a work in progress," Koetter said. "I think Mike Tice and (assistant) Wade Harman have done a really nice job coaching those guys considering that there are five guys that we were counting on down in the training room."

But Koetter couldn't say enough about Schraeder and Stone in regard to filling in for the injured players.

"Ryan Schraeder's a feisty competitor and he's going to go out there and fight," Koetter said. "And James Stone, if people knew all the stuff a center has to know. Next to the quarterback, he's doing the next most amount of talking out there on the field and, after you break the huddle, maybe more. So with all that that kid's had to learn, his mental sharpness (and) the way he picks things up. And then, the fact that he doesn't look hesitant at all out there. He's playing physical. We couldn't be more pleased.

"But it's a new week with new challenges."

The line will be challenged Sunday at Carolina, although the Panthers will be without defensive end Greg Hardy, who had four sacks and eight quarterback hits in the last meeting.

"He's a top-flight player," Koetter said of Hardy. "It's hard to put a percentage on how much it's changed (them). But every team in the NFL, when they're missing guys, when they're missing top guys for whatever reason they're missing them, it hurts them."

Even without Hardy and defensive tackle Star Lotulelei, who will miss the game with an ankle injury, the Panthers are capable of bringing pressure. Charles Johnson has given the Falcons fits over the years and sacked Matt Ryan three times last year.

"He's one of the top pass-rushers in the league," Koetter said of Johnson. "He's got great power. He's got the speed to run by you. He's one of those guys if you're sitting there waiting for his moves, he's liable to pick you up and throw you into the quarterback."

If the line gives Ryan another time to throw, Ryan could pick apart the Panthers' rebuilt secondary, which includes Falcons castoff Thomas DeCoud and 31-year-old veteran safety Roman Harper.