MORGANTOWN, W.Va. -- West Virginia's offense looked as if it was still on summer vacation for most of the first half. Then quarterback Geno Smith got the Mountaineers moving against an FCS opponent in his first career start.

Smith threw two touchdown passes and showed maturity in the pocket, while Noel Devine rushed for 111 yards and a score, leading No. 25 West Virginia to a 31-0 win over Coastal Carolina on Saturday.

The Mountaineers crawled to a 10-0 halftime lead before an offense led by Smith and Devine scored on three of its first four drives of the second half, and the defense didn't allow Coastal Carolina inside the 20-yard line all game.

West Virginia earned its first shutout since a 38-0 win at Cincinnati in 2005 and its first home shutout win since beating Rutgers 48-0 in 1997.

"I'm pleased with the way our defense played, reacted and took control of the game," said West Virginia coach Bill Stewart.

Defensive lineman Scooter Berry summarized the effort with a simple message on his Twitter account: "Doughnut."

The defense might be counted on to duplicate the effort until the offense can put together a complete game.

Smith said he was simply trying to execute a game plan, one that wasn't working too well early. The Mountaineers scored on only two of their seven first-half drives.

"We just had to stay patient," Smith said. "It wasn't like we weren't moving the ball."

Smith, who played in five games a year ago in relief of Jarrett Brown, completed 20 of 27 passes for 216 yards before taking a seat early in the fourth.

"There were a couple of throws that I wished I could have thrown better and made better reads, but it was something that we could learn from as an offense," Smith said. "I think overall as a team, we did a great job."

Unlike his three predecessors, Smith didn't have to worry about running the ball.

That job belonged to Devine, who was bottled up by the Coastal Carolina defense for much of the game. He was averaging only 3 yards per carry until breaking free for a 39-yard gain early in the fourth quarter to set up his 4-yard TD run one play later for the final margin.

The Chanticleers' focus on Devine allowed Smith to thrive, although most of his completions came on short, simple routes.

Robert Stands forced Adrian Sullivan to fumble the second-half kickoff and West Virginia's Darwin Cook recovered. Smith threw a dart to Jock Sanders in the end zone from 17 yards out on third down for a 17-0 lead.

Sophomore Tavon Austin, hoping to become more than just a return specialist for the Mountaineers, showed his speed at wide receiver against the Chanticleers.

Austin made a nice run after a catch over the middle for a 13-yard gain late in the second quarter, but he fumbled the ball through the end zone near the right sideline. He turned another short pass into a 33-yard gain that led to Ryan Clarke's 1-yard TD run for a 24-0 lead late in the third.

Austin finished with five catches for 90 yards. Sanders had eight receptions for 71 yards.

"The object was to get the ball in our playmakers' hands and I think that's something that we did today," Smith said.

Devine touched the ball nine times on a 16-play drive to open the game and West Virginia needed Smith's 4-yard scoring toss to J.D. Woods on fourth down to avoid coming up empty.

Using Devine as a decoy, Sanders went 31 yards down the right sideline on a reverse to set up a short field goal midway through the second quarter.

The rest of the first half was a struggle for the Mountaineers.

"I don't want to make excuses for Geno, but this was his first complete game and he's a sophomore," Stewart said. "He'll get better and he's my guy."

Coastal Carolina was limited to 186 yards of offense but will go home with a $350,000 payout.

The closest the Chanticleers of the Big South Conference came to scoring was after Dominique Davenport returned an interception 37 yards to the West Virginia 21 late in the second quarter, but Brandon Hogan intercepted Zach MacDowall in the end zone on the next play.

MacDowall went 13 of 26 for 119 yards.

Coastal Carolina's Justin Durham missed field goal tries of 47 and 42 yards.

"I told our guys that this will be the best team we face all year," said Coastal Carolina coach David Bennett. "Great first half, but there's two halves to football and we've got to be able to play both halves."

West Virginia won its seventh straight season opener and improved to 11-0 against FCS opponents since 2000.