GLENDALE, Ariz. -- When it was over, the confetti on the ground and another trophy raised in the air, Alabama coach Nick Saban had only one thing left to do.
"I'm smiling," he said.
Ol' sly Saban was smiling early in the fourth quarter, too, when the Crimson Tide pulled of a gutsy onside kick with the game tied at 24.
Alabama rode the momentum from that surprise to score the go-ahead touchdown and then rocket back to the top of the college football world, winning its fourth national title in seven years Monday night by beating Clemson 45-40.
The Tide used a quartet of scoring plays that covered 50-plus yards -- including a 95-yard kick return in a wild fourth quarter that featured a combined 40 points -- to deliver Clemson its only loss of the season.
"What a year. What a year," said Clemson coach Dabo Swinney. "I'm incredibly proud of our team. I think at least the nation saw why we have been so successful -- they saw the heart of our team. I think they gave us everything they had."
Heisman-winning running back Derrick Henry sealed the outcome with a 1-yard touchdown run with 1:07 remaining, stretching Alabama's lead to 45-33.
The Tigers battled to the end. Quarterback Deshaun Watson's 24-yard touchdown pass to tight end Jordan Leggett with 12 seconds left brought Clemson within a score, but the ensuing onside kick went out of bounds.
Alabama unleashed tight end O.J. Howard as a weapon to complement Henry's power running. Howard had five catches for 208 yards and two touchdowns, his first scores since the 2013 season.
Howard's second touchdown came after defensive back Marlon Humphrey recovered a high-bouncing onside kick toward the right sideline with the score tied at 24. The TV cameras caught Saban with a big grin on the sideline.
"We call it pop kick," Saban said.
"I thought we had it in the game anytime we wanted to do it. I made the decision to do it. The score was tied ... and we were tired on defense. We weren't doing a great job of getting them stopped.
"I felt like if we didn't do something to change the momentum of the game that we wouldn't have a chance to win it."
Henry ran 36 times for 158 yards and three touchdowns, including a 50-yard burst to start the scoring.
He wasn't able to get untracked much in the second half, but quarterback Jake Coker connected on scoring passes of 53 and 51 yards to Howard after the break. Coker finished 16-for-25 for 335 yards.
Alabama's fireworks on offense were enough to offset a brilliant effort from Watson, who dazzled with his arm, his legs and dizzying improv skills.
He completed 30 of 47 passes for 405 yards and four touchdowns, and he ran 20 times for 73 yards.
"He's special," Swinney said.
After several big-bowl blowouts, Alabama (14-1) and Clemson (14-1) put a whopper of the topper on the college football season in front of 75,765 at University of Phoenix Stadium.
Alabama, which lost in last season's playoff semifinals, was not done exerting its special teams superiority after the onside kick.
Clemson used a 31-yard field goal to get within 31-27, but Alabama kick returner Kenyan Drake carved through the coverage on the ensuing kickoff, taking it 95 yards and stretching out the ball to hit the pylon for a touchdown with 7:31 left.
"I think special teams may have been the difference in the game," Saban said. "The onside kick and the kick return for the touchdown kind of changed the momentum of the game."
The Tigers had won 51 consecutive games when leading after three quarters but couldn't hold on against Alabama after taking a 24-21 lead into the final period.
Saban won his fourth national title at Alabama and fifth overall. Only former Crimson Tide coach Bear Bryant (six) has won more than four national titles during the wire-service era (since 1936).
"I've never been prouder of a group of young guys," Saban said.
Alabama took a 21-14 lead early in the third quarter when Howard scored on a 53-yard reception, wide open down the right sideline because free safety T.J. Green failed to come over in support.
"It was a slugfest out there," Swinney said. "A couple of those special teams plays were momentum plays. Championship football is a game of a few plays, and that is what this came down to -- just a few plays."
Clemson took a 24-21 lead on a 60-yard drive, capped by a 1-yard plunge from running back Wayne Gallman.
Henry and Watson took turns throwing haymakers in a riveting first half, which ended with the teams tied at 14.
Henry scored twice, including on a 50-yard run, and Watson fired two pretty touchdown passes to freshman receiver Hunter Renfrow. Henry went over the 100-yard mark with 7:41 to go in the second quarter.
Each team missed 44-yard field goals, including Clemson in the final seconds of the half. Alabama defensive lineman D.J. Pettway got a hand on the attempt, causing it to fall short.
Alabama safety Eddie Jackson, who intercepted Watson in the first half, was chosen the Defensive Player of the Game. Howard won the award for offense.
NOTES: Next season's national title game will be held at Raymond James Stadium in Tampa, Fla., on Jan. 9. The semifinals will be held in the Fiesta and Chick-fil-A bowls on Dec. 31. ... Clemson DE Shaq Lawson, who sustained a sprained left MCL in the Orange Bowl, was in the starting lineup, playing with a brace on his knee. He had two sacks in the first half. ... Clemson CB Mackensie Alexander, who was nursing a hamstring injury, also started but left the game with 7:41 to go in the first half. He did not return. ... Alabama RB Derrick Henry scored a touchdown in his 20th consecutive game, an SEC record. Henry also passed Shaun Alexander (3,565 yards) as the school's leading career rusher. ... Former Alabama Heisman-winning running back Mark Ingram was the Tide's honorary captain for the game. Ex-Clemson running back C.J. Spiller held that role for the Tigers. ... A Pac-12 crew officiated the game.