CLEMSON — It’s every defensive coach’s worst nightmare.

Either it’s fourth-and-forever, or there’s no time left on the clock and the Hail Mary deep ball is in the air, and it’s football’s version of match point.

The cluster of defensive backs has one objective, and one objective only: nobody scores. Whether that means an interception, an incompletion, a tackle before the end zone … anything besides a touchdown or defensive penalty will suffice.

Auburn’s Ricardo Louis caught the most improbable of game-winning touchdowns Saturday when two Georgia defensive backs tried to make a play on Nick Marshall’s long arching throw down the field on fourth-and-18 with under 30 seconds remaining and the Tigers trailing by one point. The ball was tipped upwards, allowing Louis to make the easy catch and trot in for the go-ahead score in Auburn’s 43-38 triumph.

Recently in NFL games, the Ravens and Packers each allowed Hail Mary tries to be converted when defensive backs didn’t use proper fundamentals.

So how does Clemson teach its secondary to not turn a routine clinching play into a heart attack?

“There’s nobody behind you, first of all. And let’s knock the ball down. It’s really not complicated. Just knock the ball down,” Clemson head coach Dabo Swinney said. “That’s why you teach that, because crazy things can happen.”

Added defensive coordinator Brent Venables, bluntly: “Ball’s in the air, man, just get it down.”

For any Clemson defenders who might not have seen the Auburn play, Venables will see to it they do. He recalled the Tigers’ victory Sept. 19 at North Carolina State, when the last play of the first half nearly resulted in a 56-yard passing touchdown for the Wolfpack.

“It’s funny they came in, aww, (the Georgia players) should’ve knocked it down,” Venables said. “We’re like, yeah, that happened right before NC State at half, and I remember every one of you guys here trying to catch the ball, like there’s nobody else.”

Calm before the storm

The way the schedule shook out this year, No. 7 Clemson could face a lesser-stress matchup the game before South Carolina week.

The Citadel (5-6) will be the Tigers’ tuneup, just as Coastal Carolina stands in No. 11 South Carolina’s way on Saturday. Clemson hasn’t lost to The Citadel since 1931 (a 15-game streak), while the Chanticleers and Gamecocks have never faced off.

“I think it’s good for both South Carolina and Clemson. Maybe not necessarily to play an FCS, but maybe a mid-major or something like that,” Swinney said. “Just hasn’t been the case for us.”

Clemson had to deal with its ACC finale immediately before South Carolina each of the last six years, ever since a pre-USC bye week in 2006. The last time Clemson didn’t face an ACC opponent directly before the Gamecocks was a 1979 trip to Notre Dame.

“We’ve been battling to win the division, it seems like every year,” Swinney said, “or maintain against a conference opponent.”

South Carolina hasn’t played its SEC finale seven days preceding the Clemson game since 2005. This is the fourth straight year the Gamecocks face a mid-major or FCS opponent the week before taking on the Tigers; from 2007-09, USC utilized a bye week to prep for its biggest rival.

“I definitely think it’s preferable,” Swinney said, “to have your conference play behind you and to be able to focus on finishing your non-conference the best possible way.”

In preparation for other rivalry games Nov. 30, No. 2 Florida State plays Idaho and Florida has Georgia Southern to get ready for each other. Top-ranked Alabama hosts Chattanooga while No. 6 Auburn has a bye week before the Iron Bowl.

Drama king

So maybe quarterback Tajh Boyd was slightly embellishing the severity of his injury Thursday night at Georgia Tech, which had Clemson fans everywhere holding their breath as he laid on the Memorial Stadium turf.

“I probably was a little more dramatic than I needed to be,” Boyd admitted Tuesday. “But yeah, your thoughts definitely flashed. In my mind, I was like, this can’t be my last game I play here at Clemson. Fortunately, everything worked out.”

Boyd has a bruised sternum, but avoided a broken collarbone.

Don’t forget

While it’s good that Clemson gets both its games facing a triple option offense back-to-back, the disadvantage is the Tigers must abruptly revert to traditional schemes when they do turn their attention to South Carolina the following week.

“It’s not easy to manage, and I don’t know whether we have the answers for that,” Venables said. “We still do a decent amount of good-on-good. I would be surprised if we forgot everything we’ve learned up to this point.”