CHAMPAIGN, Ill. -- Penn State needed a half to wake up on offense before running all over Illinois.

Backup tailback Stephfon Green ran for 120 yards and one touchdown and starter Evan Royster added 105 yards and a score as the 15th-ranked Nittany Lions scored 28 second-half points to trounce Illinois, 35-17, yesterday.

Quarterback Daryll Clark also contributed 83 yards rushing and two touchdowns and third-string tailback Brent Carter added a late score as the Lions (4-1, 1-1 Big Ten) finished with a season-high 339 yards on 40 carries and an 8.4 average against the Illini (1-3, 0-2).

It marked the first time since the 2005 season that Penn State had two 100-yard rushers in the same game.

"It's a great accomplishment for our offense," said Royster, who had 17 carries, a 6.2 average, and a 15-yard touchdown run. "We're really excited to get it done. We blocked real well up front today."

Green, who had just 70 yards in the first four games, finished with a career-high 13 carries while averaging 9.2 yards. His 52-yard touchdown run in the second quarter gave Penn State a 7-0 lead.

Right guard Lou Eliades pulled left on the play and knocked Illinois linebacker Russell Ellington out of the way, creating a huge hole for the speedy Green to go through and reach the end zone untouched.

It was the longest running play of the season for Penn State and the longest scoring run since Green went 69 yards for a touchdown against Temple last season.

"Lou came to play today and so did the offensive line, which opened up a lot of holes," Green said. "Evan and I just saw the holes today and we hit them. We were just very patient."

Royster posted his eighth career 100-yard game, while Green notched his second. Green had 81 yards on seven carries in the second quarter alone.

"He's got all the speed in the world and you saw it on the touchdown run," Royster said. "It got us going."

Penn State's previous rushing high this season was 186 yards against the Owls in the third game. And its total of 338 yards was the most since the Lions accumulated 334 in the 2008 opener against Coastal Carolina.

"I think we did a little better job with the run selections today," coach Joe Paterno said. "I think some of the kids got a little bit embarrassed that we haven't done better for a full game."

Penn State's maligned offensive line underwent yet another lineup change, with Nerraw McCormack replacing DeOn'tae Pannell at right tackle. That revamped unit helped pave the way for 241 yards rushing in the second half and four of the five rushing touchdowns.

"Yeah, I don't think we really did anything crazy or different," center Stefen Wisniewski said. "We kind of just eliminated that mistake here or there that was holding us back."

Clark, who averaged 11.9 yards rushing on seven carries, ran for 82 yards in the second half, including a career-long 51-yarder. He scored on two 1-yard sneaks.

"I was just trying to pick a hole and do whatever I could," said Clark, who had just 17 yards rushing on 16 carries the first four games. "I was just trying to open some things up."

Clark's scrambling did just that. His short plunge at 6:34 of the third quarter broke up a tight game and gave the Lions some breathing room at 14-3. His second score at 14:28 of the fourth quarter put the game away.

Penn State finished with 513 yards offense and Clark completed 17 of 25 passes for 175 yards.

"Daryll rarely says, 'We should throw the ball more,' or 'We should run more,'" Paterno said. "He's a team player. I think he showed he could run. We always knew he could run. We will probably take more chances with Clark as we go along."

NOTES -- Outside linebacker Sean Lee was in uniform, but he sat out his second game with a sprained left knee. Bani Gbadyu made his second consecutive start in Lee's absence. ... Wide receiver/kick returner Devon Smith (concussion) did not play. ... The defense has not allowed a first-half touchdown this season. ... The Lions recorded three sacks (Eric Latimore, Jack Crawford and Sean Stanley), an interception (Stephon Morris) and recovered a fumble (Jared Odrick). ... Doug Whaley, pro personnel coordinator for the Steelers, attended the game.

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