CLEMSON, S.C. — Every year before fall camp, Eric Mac Lain’s grandmother asks him how the team is looking. Every year, the Clemson left guard says he will let her know in three days.

This year’s camp, Mac Lain’s fifth with the Tigers, seemed unlike the previous four. He couldn’t quite explain it, but he felt confident in telling his grandmother — an Alabama fan, it should be noted — that things were clicking up front.

“Three days into camp, I just felt it,” Mac Lain said. “There was something different. We weren’t starting over, we were starting from where we left off in spring, and guys just dominated throughout camp and it was just exciting to see.”

Internally, perhaps, Clemson saw this coming — the unbeaten ACC campaign, the No. 1 national ranking, the Heisman consideration for its star quarterback. Externally, even, it all hardly seemed like a stretch; the Tigers and Deshaun Watson were the overwhelming preseason media favorites to win the ACC title and league player of the year award, respectively.

So much of that, though, hinged on Watson’s health, which hinged on his offensive line, which, when summer attrition had its final say, left the Tigers with one returning starter.

Fast forward to the ACC finale, and here Clemson is, in Dabo Swinney's words, as the “No. 1 team in America, whatever that means, but we had two true freshmen at tackle." And that aforementioned returning starter, Ryan Norton, has missed seven games with a sprained knee.

Eight different players have helped the Tigers make up four different starting offensive line combinations through 11 games.

"The group that was challenged the most coming into the season," co-offensive coordinator Tony Elliott said of the line. "Some people viewed it as a weak link, and all they did was go to work, and now they’re the reason we’re having success offensively where we’ve had an opportunity to have seven games in a row where we put up some pretty good offensive numbers."

Clemson leads the ACC in total offense and is second in scoring. The Tigers are third in rushing. They are doing this after their most-experienced player, starting left tackle Isaiah Battle, left in June for the supplemental draft, forcing Mitch Hyatt into starting action from Day 1.

Fortunately for the Tigers, Hyatt had been a five-star prospect. And he happened to be a 6-foot-5, 295-pounder who had already begun to prove himself to teammates after enrolling in the spring.

"Mitch came in and he was almost technically sound, which is very rare,” Norton said. “Great technique coming in, his kit was great, he knew how to pace his sets, which is very unique for a freshman to know. And then as he grew and he got stronger obviously during the summer and winter workouts and all that, it was just unbelievable. We could see it. Intellectually he has it. Technique-wise he has it.

“Obviously he’s a freshman, so he can fix a few things. But we had faith in him 100 percent from the get-go, even when Isaiah was still here. [Hyatt] had shown that he was going to be a very good player.”

Perhaps as important, the Tigers say, is the evolution of Watson’s command. Last year, he, like Hyatt, was a blue-chip prospect who got a head-start by enrolling early. This year, with everyone having already seen flashes of his capabilities, Watson was ready to take the next step.

Mac Lain has compared Watson to Peyton Manning in his ability to check out of plays at the line. Hyperbolic as that may sound, the staff does not shy away from the analogy.

“It’s improved every week, and the reason being is because Deshaun speaks their language,” Elliott said of the line and quarterback’s relationship. “He’s the quarterback, he understands the protections, he understands what we’re trying to get accomplished. He knows when to let Jay make the call and he also knows when to override Jay’s call to get us all on the same page because he can see the big-picture.”

Jay is Jay Guillermo, who was thrust into the starting center role when Norton went down before Week 3 and never really looked back. Even that, though, has led to Norton taking Guillermo under his wing, which speaks to the chemistry of the group.

As for the depth: freshman Jake Fruhmorgen started at right tackle on Saturday as Joe Gore tended to a personal issue. Maverick Morris has started the last two games at right guard for Tyrone Crowder, who has dealt with turf toe.

Swinney insisted before the season that, despite the outside trepidation, Robbie Caldwell was the happiest guy in the room. The offensive line coach, Swinney said, knew what everyone else soon would learn — that this line was more than good enough, that it could go from a unit holding the ACC favorite back to one helping lift it to the brink of the College Football Playoff.

“This game is about the trenches, it really is,” Swinney said. “You have to have a great quarterback, and we definitely have that. But you have to have some guys in the trenches. Your quarterback can get real average real quick if you’re a one-dimensional football team. And we’re not. We’re a team that can run the ball, we’re a team that can throw the ball, and that’s a credit to our offensive line.”