UNIVERSITY PARK, Pa. -- Evan Royster made his debut as Penn State's No. 1 tailback Saturday at the Blue-White spring game at Beaver Stadium.

But it was Royster's backup, Stephfon Green, who stole the show.

Green's game-breaking speed -- he has been timed at 4.25 seconds in the 40-yard dash -- was evident on his first carry.

He took a toss from backup quarterback Pat Devlin on the third play of the scrimmage and scampered off left tackle for 57 yards and a touchdown against the first-team defense.

Green slipped a tackle by starting safety Anthony Scirrotto near the left sideline and then outran cornerback Tony Davis to the end zone.

The touchdown run and subsequent celebration ended a year of misery for the 5-foot-10, 189-pound redshirt freshman from the Bronx, N.Y.

"I pouted last year when [the coaches] told me they were going to redshirt me," he said. "Every game I cried. I wanted to be out there. I felt I could help my team to a championship, but they had experience in front of me.

"I couldn't wait until I played in front of 70,000 or 80,000 people. Now I just can't wait until I play in front of 110,000 [this fall]. I couldn't wait until the spring game. According to you guys, I lit it up."

In addition to the touchdown, Green managed a game-high 87 yards on 12 carries for the White team, which lost to the Blue, 27-14. He averaged 7.2 yards per carry and added three catches for 19 yards.

"He's very electrifying," starting quarterback Daryll Clark said. "Speed, speed and more speed. He showed me that he can run the ball, and if you give him a crease, he's gone."

Royster, a redshirt sophomore from Fairfax, Va., who averaged 6.3 yards per carry last year while backing up 1,000-yard rusher Rodney Kinlaw, had only 24 yards on three carries and one touchdown Saturday.

Royster will enter the fall as the starter, but look for Green to push him for playing time.

Royster experienced a similar situation a year ago, when many thought he might replace Kinlaw, who took over at tailback in October after Austin Scott was kicked off the team.

"It's [Stephfon's] first year coming out and getting a chance to play, so people are going to be talking about him," Royster said. "I'm sure Rodney felt the same way last year. People were talking about me when I started to play."

Royster, 6-1, 212, was the Nittany Lions' second leading rusher last season, gaining 513 yards on 82 carries. He also scored five touchdowns, including the winner in the Alamo Bowl victory against Texas A&M. He was named to The Sporting News' Big Ten all-freshman team.

"Royster is one of those guys that's already proven himself on the field," left tackle Gerald Cadogan said. "We know he can get the job done. Stephfon Green has great potential. He has that spark. He can go the distance if he gets in the open field."

It's possible Royster and Green could end up in the backfield together this season. There's also a chance one or the other could line up in the slot as a receiver.

"Stephfon brings a different aspect to our team with his speed," Royster said. "He opens things up for me. I can suck the defense in with the inside run, and he can break it outside.

"You've got two completely different style of backs."

Green appeared comfortable in the spotlight.

"I'm just having fun," he said. "I look forward to four more years of this."