Clemson scored 21 points in the fourth quarter of the College Football Playoff National Championship Game to come from behind and shock unbeaten Alabama, 35-31.

After Alabama took a 31-28 lead on a 30-yard Jalen Hurts touchdown run with 2:07 to go, the Tigers went 68 yards in nine plays to score the game-winning touchdown with just a single second left on the clock.

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There were three key plays on that final drive that put Clemson on top, but two other plays were also crucial in giving the Tigers the second national title in program history.

Hunter Renfrow two-yard touchdown catch

This is the play that won it all. After a pass interference play set up first-and-goal from the Alabama 2-yard line with just six seconds to go, Clemson knew it had one more play to try to win the game. If not, a chip shot field goal would force overtime.

Star quarterback Deshaun Watson looked toward Hunter Renfrow, who already had nine catches and a score on the night. Renfrow, a former walk-on, ran a quick out route, and got a controversial pick from Artavis Scott, leaving him wide open. Watson delivered a perfect ball, giving the Tigers a lead with just one second to go.

“We got man coverage, like we needed to get right there,” Tigers head coach Dabo Swinney said. “They did a great job setting the route up, and Renfrow popped loose, and (Watson) delivered the ball and it was an unbelievable moment.”

Added Watson: “I knew before I even snapped the ball it was going to be a touchdown. All I had to do was just get the ball to him. I slowed down the moment, everyone made their blocks and did their part, and I did my part, and we pulled it out.”

Now, that play will go down in college football history.

Jordan Leggett 17-yard catch

Before the Watson-to-Renfrow heroics, tight end Jordan Leggett made an awesome catch to move the Tigers inside the Alabama 10-yard line.

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The play came after Watson spiked the ball at the 26 to stop the clock with 19 seconds remaining. Watson received the shotgun snap and with the ferocious Alabama pass rush in his face, he delivered a strike to Leggett. Leggett had a crucial drop earlier in the fourth, but redeemed himself by reaching back on a back-shoulder throw in front of Ronnie Harrison.

Leggett’s final catch was his seventh and gave him a team-leading 95 yards for the game. Two plays later, the Tigers were national champions.

Mike Williams 24-yard reception

Five plays before Leggett’s clutch grab and after Alabama QB Jalen Hurts’ touchdown scamper put the Tide back in front, Clemson’s offense had to regroup. On the second play of the ensuing drive, Watson looked to his favorite target: Mike Williams.

Williams missed the College Football Playoff last year because of a neck injury. He was healthy this time around and came up big all game long. On this play, with 1:56 left in regulation, Watson looked Williams’ way down the left sideline. Williams used his 6-foot-3, 225-pound frame and showed why he is likely a first-round pick.

Williams leaped high above Alabama DB Anthony Averett and made a ridiculous catch to move the Tigers all the way to the Tide’s 39-yard line.

That play would set the tone for the entire drive.

Deshaun Watson’s pooch punt

Watson proved yet again why he is the nation’s best quarterback, but a play he made with his foot, not his arm, ended up being huge for the field position battle.

Trailing 17-7, the Tigers moved to the Alabama 43-yard line and Swinney had a decision. On fourth-and-1 with 9:14 left in the third, Swinney sent his offense out onto the field, but instead of going for the first down, Watson received a shotgun snap and calmly punted the ball down to the 5-yard line.

Alabama seemed to really control the field position for a lot the game to that point, so pinning the struggling Tide offense that deep in its own territory changed things. Clemson quickly forced a three-and-out on the ensuing drive and regained possession in Alabama territory. Four plays later, the Tigers cut the Alabama lead to 17-14 on Watson’s 24-yard touchdown pass to Renfrow.

Oh, and guess who was the Tiger to down that Watson punt?

Renfrow. Again.

Hunter Renfrow tackle on Ryan Anderson strip, fumble recovery

Trailing just 14-7, Clemson began the second ball with the half but its drive quickly went south. On the fourth play of the drive from Clemson’s own 38, Watson handed off to Wayne Gallman and Alabama star linebacker Ryan Anderson swooped right in. Anderson ripped the ball right from Gallman’s hands and scooped up the loose ball at the 28 with a head of steam toward the end zone.

Alabama had 15 non-offensive touchdowns on the season and Anderson looked like he would add another. Renfrow, before his fourth-quarter heroics, had other ideas.

He sprinted in from his wide receiver position and had a good angle on Anderson. He was able to cut Anderson down, stopping what was likely an Alabama score.

From there, the Clemson defense held the Tide without a first down and forced a short field goal try. Those four points would certainly make a difference later on, huh?

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Sam Cooper is a writer for the Yahoo Sports blogs. Have a tip? Email him or follow him on Twitter!

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