Penn State football coach Joe Paterno, his arm in a sling, rides in a cart at practice Wednesday. The 84-year-old Hall of Famer injured his shoulder and pelvis after a receiver blindsided him during drills Sunday. He spent almost two days at a hospital before being released Tuesday.

STATE COLLEGE — Now that Joe Paterno has returned to practice, he can refocus his attention to Penn State’s defense.

Just like its leader, Linebacker U. is eager to rebound from injuries.

A picture on the team’s web site showed a smiling Paterno on a golf cart at practice Wednesday afternoon, his right arm in a sling.

The Hall of Famer injured his shoulder and pelvis after a receiver blindsided him during drills earlier this week. He spent almost two days at a hospital before being released Tuesday, saying in a statement he wanted to shift the attention back to his team.

The Nittany Lions apparently didn’t miss a beat at practice without him.

“For us, it’s business as usual,” linebacker Michael Mauti said this week. “Our assistant coaches have been there before. We know where we need to go and our goals, whether Joe is there or not. I think he would want us to do the same thing ... Keep our heads down and keep working.”

Last year, the defense didn’t live up to its typical lofty standards. Penn State was seventh in the Big Ten against the run (165 yards per game) and tied for eighth in sacks with 17.

They were also porous in the red zone, allowing opponents to score a league-worst 91 percent of the time (34 of 37) inside the 20.

Paterno put much of the blame on himself.

“I don’t think we played very well last year. I don’t think I did a very good job coaching last year, to be frank with you,” Paterno said last month at Big Ten media day in Chicago. “I’ve got to do a better job. Everybody’s got to do a better job.”

The energy level has apparently been turned up in camp, according to postings from players on Twitter. Mauti, a redshirt junior, said the first week was the most intense so far in his career.

“It’s a lot of running, a little more than we’re used to,” he said. “Joe says this is how hard we need to win, so we just buy into that. ... We’ve taken the attitude, `Whatever it takes.”‘

At certain times last season, the Nittany Lions had enough trouble just keeping up with the injury report. Ends Jack Crawford (right foot) and Eric Latimore (left wrist) were among those sidelined, as was starting safety Nick Sukay, who had a chest injury.

The linebacker position took a hit, too, with Gerald Hodges and Mauti also missing some time.