ATHENS, Ga. — Mark Richt tried to treat Todd Gurley's three-touchdown debut with a casual attitude.

Gurley, the freshman playing in his first college game, ran for 100 yards and returned a kickoff 100 yards for score, and No. 6 Georgia overcame a sloppy first half to beat Buffalo 45-23 on Saturday.

Gurley didn't start but may have emerged as the Bulldogs' future at tailback with eight highly productive carries, including scoring runs of 10 and 55 yards.

Richt said Gurley had been similarly impressive in preseason scrimmages.

"He averaged about what he averaged every scrimmage, about 12.5 yards per carry," Richt said. "I hope that's a trend in his career."

Georgia, favored by 37½ points, led only 24-16 at halftime before pulling away in the season opener for both teams.

It was not an impressive showing by Georgia's defense. The visiting Bulls of the Mid-American Conference are coming off a 3-9 season that included a 41-10 loss at Tennessee, but they ran 70 plays and had 199 yards rushing against Georgia.

The Bulldogs play at Southeastern Conference newcomer Missouri next week.

"It wasn't pretty," Richt said. "We better play better than that next week, or we'll be coming back sad."

Gurley's play was the highlight for Georgia fans.

"He showed why he's special," said Georgia senior receiver Tavarres King, who had six catches for 117 yards and a touchdown. "He'll make the most of his opportunities."

Gurley (6-1, 218) showed both power and speed as he became Georgia's first freshman to run for 100 yards in his first game since Danny Ware ran for 135 yards against Georgia Southern in 2004.

"I didn't have time for butterflies; everything just came so fast," Gurley said. "I was just trying to get the plays right. I really didn't have time to get nervous."

Asked to rate his debut, Gurley said "I can't complain. ... It felt pretty good."

The Bulldogs entered the season unsure who will be their lead tailback after Isaiah Crowell, last season's freshman star, was kicked off the team.

In this game, it looked as if Georgia has plenty of options.

Another freshman, Keith Marshall, had 10 carries for 46 yards and starter Ken Malcome had six carries for 32 yards before hurting his left hand in the third quarter.

Branden Oliver, coming off his school-record 1,395 yards rushing in 2011, had 30 carries for 111 yards and a 2-yard touchdown run for the Bulls.

"Their defense was really hyped up, but we had a lot of confidence coming into this game," Oliver said. "We came to play. We thought we had a chance to win."

Buffalo's Alex Zordich completed 14 of 24 passes for 148 yards, including a 16-yard touchdown pass to Alex Neutz in the first quarter. Zordich added 14 carries for 83 yards, including a 2-yard touchdown run late in the game.

Zordich led first-half scoring drives that covered 75 and 84 yards.

"To be able to come up with a 94-yard drive against one of the best defenses Georgia has had in a while gives us some great confidence that we can move the ball when we put our minds, heart and soul into it," said Buffalo coach Jeff Quinn.

Murray completed 15 of 26 passes 258 yards with three touchdowns and no interceptions. After his sluggish opening half, Murray threw scoring passes of 38 yards to Rantavious Wooten in the third quarter and 12 yards to Michael Bennett in the fourth.

Murray, a junior opening his third season as the starter, struggled early in the game with accuracy, often overthrowing receivers. He was on target for a 63-yard touchdown pass to King, giving Georgia a 24-6 lead in the second quarter.

Georgia ranked fifth in the nation in total defense in 2011 but was missing several starters due to suspensions and injuries.

Three starters — safety Bacarri Rambo, linebacker Alec Ogletree and cornerback Sanders Commings — were held out with suspensions. Richt confirmed the Rambo and Ogletree suspensions after the game.

Georgia previously announced Commings and outside linebacker Chase Vasser would serve two-game suspensions after offseason arrests. The other suspensions were for violations of team rules.

Richt said "we'll find out next week" about the status of Rambo and Ogletree for the game at Missouri.

Georgia also was without cornerback Malcolm Mitchell, who was on crutches after spraining his left ankle in Thursday's practice, and wide receiver Marlon Brown, who has a strained left hamstring.

Freshman left tackle John Theus left with a sprained left ankle in the fourth quarter.

Buffalo also was missing a top defensive player. Linebacker Khalil Mack served a one-game suspension for violating team rules.