STARKVILLE (AP) — Dak Prescott spent the second half of his debut as Mississippi State’s starting quarterback standing on the sidelines, giving out high-fives and laughing with teammates.

He was so good during the first half, he wasn’t needed on the field.

The sophomore threw for 174 yards and two touchdowns and ran for a touchdown as the Bulldogs built a huge halftime and breezed past Alcorn State 51-7 on Saturday afternoon.

“We got in a rhythm, we were comfortable and everybody did a good job,” Prescott said. “Everybody did their 1/11th out there.”

Mississippi State (1-1) didn’t use several regular starters, including quarterback Tyler Russell, who suffered a concussion in the Bulldogs’ season-opening loss to Oklahoma State.

It didn’t matter. The Bulldogs led 21-0 by early in the second quarter and 37-0 by halftime. It was the most points in the first half for the program since 1996.

The 6-foot-2, 230-pound Prescott has the reputation as an effective runner but inconsistent passer. He looked more than capable against the Braves, completing 12 of 19 passes, including a perfect 14-yard strike to Derrick Milton in the front corner of the end zone for his first passing touchdown of the season.

Mississippi State coach Dan Mullen said Prescott did everything he was asked. Prescott played in 12 of 13 games last season as a backup.

Mullen said he hopes Russell can return for the Bulldogs’ first Southeastern Conference game next weekend against Auburn, but Prescott looked comfortable leading the offense in his absence.

“He made some good reads, managed the offense well, made plays when we needed him to make them and I’m proud of that,” Mullen said.

Mississippi State freshman Ashton Shumpert rushed for 98 yards and two touchdowns. Nick Griffin added 53 yards on the ground and a touchdown.

Alcorn State (1-1), which plays in the Football Championship Subdivision, had two first downs on its first drive but didn’t get another one until the fourth quarter. The Braves scored their only touchdown on a 25-yard pass from John Gibbs Jr. to Tollete George.

Mississippi State was obviously much more talented than the Braves, but the steady stream of offense was still encouraging for the Bulldogs after an ugly 21-3 loss to Oklahoma State last weekend.

Prescott showed his poise early in the first quarter by converting two straight passes on 4th and 9 for a first down.

The first was an 18-yard strike to Joe Morrow, but it was disallowed after officials ruled Alcorn State had called timeout. A sold out Davis Wade Stadium groaned, but Prescott came right back and hit Malcolm Johnson for a 23-yard gain.

“The first one just showed me I could do it,” Prescott said. “So I just relaxed, we called a different play and I did it again.”

Two plays later, Prescott showed his running ability, bursting through the line for an 11-yard touchdown run and a 7-0 lead. The rout was just beginning.

Mississippi State outgained Alcorn State 308-30 in total yards in the first half. The Bulldogs finished with a 556-163 advantage.

The second half started just as lopsided. Brandon Holloway ran the kickoff back 95 yards to Alcorn’s 1-yard line, and Mississippi State scored two plays later on Shumpert’s first touchdown run for a 44-0 lead with 13:57 left in the third quarter.

Mississippi State freshman Damian Williams made his college debut in the second half, completing 5 of 8 passes for 69 yards and an interception.

Alcorn State’s George finished with four catches for 80 yards and the Braves’ only touchdown. Gibbs was 11 of 25 passing for 135 yards, one touchdown and one interception.

“We made some mistakes early,” Alcorn State coach Jay Hopson said. “We turned the ball over on offense. We have got to start protecting the football on offense. We can’t give them anything cheap.”