CLEMSON — Clemson's defensive players look confused when they're asked to recall the last time the Tigers made a crucial stop at the end of a game.

Just queue up the music from "Jeopardy" and watch them fidget.

"I really can't think back to a game we did make a stop we needed to make at the end," said junior end Ricky Sapp.

Said safety Michael Hamlin: "It's been a while, hasn't it?"

Yes, it's been that long since Clemson's defense produced late when it absolutely had to.

In last year's opener against Florida State, Clemson stuffed the Seminoles three times in the fourth quarter for a 24-18 victory in Death Valley. Since then, the road has been littered with games in which the defense made crucial breakdowns at the end of games.

And each of the Tigers' past three losses have been marked by late, backbreaking plays by opposing offenses. The defense has given up just five touchdowns in the losing streak, but those numbers have been overshadowed by crucial gaffes in the clutch.

The inability to come up with a stop holds particular relevance given Saturday's trip to Boston College. Last season, the Eagles scored 17 fourth-quarter points — including the game-winning 43-yard touchdown pass from Matt Ryan to Rich Gunnell with 1:46 left — to deny Clemson a trip to the ACC title game.

"That's something we've been stressing for the last three or four weeks," Hamlin said. "It seems like week in and week out coach Vic (Koenning) starts meetings by saying the offense gave us the lead in the fourth quarter, and that's something we always want — just for the offense to get the lead. Our job is to maintain it. We've been doing a pretty poor job at it."

The offense hasn't exactly held up its end of the bargain during the losing streak, having scored just three touchdowns over the past 10 quarters. But the Tigers (3-4, 1-3 ACC) have taken leads into the fourth quarter of all three games:

-- On Sept. 27 against Maryland, Clemson turned the ball over on downs with 5:36 left. The Terrapins managed to run out the clock on the 20-17 win, converting a third-and-8 and third-and-4 on two passes.

-- On Oct. 9 at Wake Forest, Clemson led 7-6 and forced the Demon Deacons into a third-and-24 at their own 8-yard line. Riley Skinner passed to D.J. Boldin for a 28-yard gain, and Wake Forest scored the go-ahead touchdown on the same drive before winning 12-7.

-- On Oct. 18 against Georgia Tech, the offense scored two third-quarter touchdowns to create a 17-14 lead. The Yellow Jackets drove for the go-ahead touchdown with 5:22 left, converting on a third-and-14 and a third-and-6, and won 21-17.

Koenning, in his fourth year as the Tigers' defensive coordinator, said inexcusable mistakes by defensive backs in those three games "changed our season." On the third-down pass against Wake Forest, safety Haydrian Lewis stumbled and was out of position. On the third-and-6 against Georgia Tech, cornerback Chris Chancellor bit on a pump fake and allowed Josh Nesbitt to complete a 24-yard touchdown pass to a wide-open Demaryius Thomas. Koenning said an unnamed safety fouled up the coverage on Maryland's final drive.

Koenning believes the more the list of late-game failures adds up, the more it becomes a psychological burden. Last year, in addition to the Boston College meltdown, the Tigers wilted late in losses to Auburn, Virginia Tech and Georgia Tech.

Clemson did make a stop late against South Carolina, giving the ball to the offense and paving the way for a drive that resulted in the game-winning field goal as time expired.

Koenning said his players "just haven't made a play" this season and have also suffered from some missed calls by officials.

Clemson ranks 85th nationally in third-down conversion defense, allowing opponents to convert 42.1 percent.

"It just hasn't gone our way," Koenning said. "We've got to make the breaks, and we can't rely on the side things. But we also can't do things that we're not supposed to or try to press or something. I think there probably is some of that. And it goes for coaching, too. How would you like to be a guy calling plays or calling defenses when you know if you give up a touchdown … that's probably the game?

"That's not fun. Whereas if you're up three or you know your offense is going to be able to go up and down the field and this and that. It puts pressure on the players. It puts pressure on the coaches."