ATLANTA -- Unbeaten Alabama is one victory away from a second straight national championship and fifth in nine seasons thanks to a breakout game from sophomore running back Bo Scarbrough and its usual dominant defense.

Scarbrough scored two touchdowns, including a 68-yarder early in the fourth quarter, and the No. 1-ranked Crimson Tide got their 11th defensive touchdown of the season in a 24-7 Peach Bowl victory over No. 4 Washington in a College Football Playoff semifinal on Saturday at the Georgia Dome.

Scarbrough's 180 yards on 19 carries was the most ever for an Alabama player in a bowl game, and his clinching run was the longest.

"Bo has really played well for us, especially the second half of the season when he got healthy," coach Nick Saban said. "We wanted to play him more. He's hard to tackle. He's big and powerful. He's playing with a lot of confidence and he did a great job for us today."

The victory, which advanced Alabama to the title game against either Clemson or Ohio State in Tampa, Fla., on Jan. 9, was the 26th straight for the Crimson Tide (14-0) -- and 16 have come against ranked teams.

"It's a little bit like running a marathon," said Saban, whose team beat Clemson for the national title last year. "You get to the 20-mile mark and you still feel like you're only halfway there. We've got more miles to go and these guys are very committed to it."

Washington (12-2) came in leading the nation in turnover margin at plus-21, but quarterback Jake Browning threw a pick-six to senior linebacker Ryan Anderson and a fumble by wide receiver John Ross set up a Crimson Tide field goal.

"They beat us with our own game," Washington coach Chris Peterson said. "When you're playing this type of game, when the margin for error is that small, those things are going to show up."

Browning, who was intercepted twice and sacked five times, finished 20 of 38 passing for 150 yards and a touchdown. Washington also had just 44 yards rushing.

"They play a little hateful out there and that's a good thing when you're playing defense," Saban said. "They did a really good job against a really good Washington offense."

The Crimson Tide didn't turn the ball over and Alabama is 39-0 under Saban when it is at least plus-two in turnover margin.

"Our goal is to take the ball away and score. That makes it easier for our offense," Anderson said.

Washington, having punted the ball to the Alabama 2-yard line, appeared to still be in the game early in the fourth quarter.

Scarbrough, though, broke off an 11-yard run on third down and then capped the 98-yard drive on his long run with less than 12 minutes remaining.

Alabama spotted Washington an early touchdown, but led 17-7 at halftime thanks to 10 points off Huskies turnovers.

Adam Griffith's tiebreaking 41-yard field goal on the first play of the second quarter came after a recovery by All-American defensive end Jonathan Allen on a fumble forced by cornerback Anthony Averett.

Then Anderson stepped in front of a pass from Browning, who was being blitzed by reserve defensive back Marlon Humphrey, and returned the interception 26 yards for a touchdown with 73 seconds left in the half.

Just like Florida in its 54-16 loss to Alabama in the SEC Championship Game, Washington burned the Crimson Tide with an early TD pass. Wide receiver Dante Pettis got behind safety Minkah Fitzpatrick for a 16-yard score to cap a 71-yard drive on the Huskies' second possession.

Alabama countered, though, with an 18-yard touchdown run at the end of a 78-yard drive by Scarbrough, who had 80 yards in nine carries at intermission.

"I've had so many injuries, it was a mind game," Scarbrough said. "But I stayed confident in myself and in my teammates."

Alabama had 269 of its 326 yards on the ground. Freshman quarterback Jalen Hurts threw just 14 passes, completing seven.

"We played the game that we needed to play on defense," Peterson said.

Washington, though, wasn't as dominant as Alabama and didn't get any turnovers.

"That defense is good," Peterson said. "I mean, you're going into this game knowing this is going to be tough sledding. This is going to need to be a low-scoring game for us to be able to win, because they're so good against the run and they might be better pass rushers."

NOTES: A home away from home, Alabama won its last nine games at the Georgia Dome, where Crimson Tide coach Nick Saban was 13-1 also counting his time at LSU. ... Next season's College Football Playoff title game will be played next door at the new $1.5-billion retractable-roof Mercedes-Benz Stadium on Jan. 8, 2018. ... The Georgia Dome was the site of 252 college football games, including 25 Peach Bowls and 23 SEC Championship Games. ... The crowd of 75,996 was a Dome record. ... Alabama and Washington first played in the 1926 Rose Bowl, with the Crimson Tide rallying for a 20-19 victory to claim their first national title. The teams' last of four previous meetings was in 1986 and Alabama won that game 28-6. ... Honorary captains were Atlanta Falcons WR Julio Jones for Alabama and former NFL S Lawyer Milloy for Washington.