When the curtain was pulled back, it was hard not to pay attention to Joe Paterno's pained gaze and the mismatched shoes.

The Penn State coach with the ailing legs was forced to watch from the coaches' box as the Nittany Lions ho-hummed their way past Purdue, 20-6, yesterday. Afterward, in the postgame interview room, the 81-year-old Paterno was asked if, because of his health, his ability to coach was week-to-week for the first time in his long career.

"Yeah, it is," he said. "And that's why I'm reluctant to really get into what's going to happen next week. Some days it doesn't bother me much at all."

Paterno injured his right leg just days before the opener when he tried an onside kick during practice. His left leg was broken two years ago when he was hit on the sideline at Wisconsin. Yesterday, he said he had a "little arthritis" in his right leg, but wasn't sure if it would require surgery.

"I don't know," he said, "but I'm not letting anyone get near me with a knife."

No. 6 Penn State is now 6-0 overall, and 2-0 in the Big Ten, while Purdue is 2-3 and 0-1.

The Nittany Lions cut the Boilermakers to pieces, even as their high-powered offense put up less than half of their average points scored (49.8) coming into the game. Credit has to go to the Lions' defense, which previously hadn't been asked to carry the load, but did so by confusing the Boilermakers' spread offense. Linebacker Josh Hall led Penn State with 11 tackles.

"Last week [against Illinois], we came out a little flat and the offense picked us up," defensive end Josh Gaines said. "Today, it was us."

Defensive coordinator Tom Bradley's defense held quarterback Curtis Painter to 112 yards through the air and drove the senior out of the game after he tossed a late third-quarter interception to Lions safety Drew Astorino.

Purdue coach Joe Tiller benched his spread-offense maestro for backup Joey Elliott. But Penn State was ahead, 20-0, by the time Elliott led the Boilermakers to their lone touchdown with 6 minutes, 28 seconds left in the game.

The Lions' high-octane offense, meanwhile, was at a half-a-tank, failing to capitalize inside the red zone. It had to settle for two chip-shot field goals from Kevin Kelly after moving inside the Purdue 5.

"You're going to have to go through games like that," Penn State quarterback Daryll Clark said.

Clark, though, was efficient. The junior threw for 220 yards on 18-of-26 passing and guided an offense that didn't turn the ball over. He also continued the habit of converting on key third downs.

On Penn State's first scoring drive - before he dived for a 1-yard touchdown - Clark hit Graham Zug for a 16-yard pass on third and 7. Then, in the third quarter, he connected with Deon Butler for 23 yards on third and 17. Evan Royster, on the next play, ran for a 4-yard score. And finally, on third and 7, Clark flipped Royster a shovel pass that went 23 yards and led to a fourth-quarter field goal.

Royster continued to impress. The sophomore running back managed a career-high 141 yards on 18 carries on a slippery field. He also chipped in with four catches for 53 yards.

The Lions' run game - 202 yards total - was more than enough against Purdue, which couldn't do much of anything, including make short kicks. Chris Summers was errant on two field-goal tries and an extra point as Tiller fell to 2-8 against Paterno, his ailing friend.

"It's tough, I guess," Penn State quarterbacks coach Jay Paterno said of his father's condition. "But he's going to be all right. It's just a matter of him fighting through week-to-week."

Paterno admitted that he needed the postgame podium to stand. The nattily dressed icon wore his typical oxford shirt, blue tie and rolled-up khakis. But his trademark black Nike cleats were replaced by black shoes. On his right foot was a tasseled loafer. Dangling from his left was a completely different loafer.

"I've taken more pills in the last two months than I've taken all my life," Paterno said. "When I was a kid and something ached, my mom threw me in the tub with steaming water and brought out the olive oil and rubbed it on my head."

Moments later, Paterno limped out of the room, down several steps, and into a waiting van.

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