Dr. Wayne Sebastianelli, the team's Director of Athletic Medicine, said Yisrael, a returning starter at the Hero position, tore the ACL in his left knee. He said Yisrael will have surgery within the next two weeks and rehabilitation will take approximately nine months.
"That's a real setback for him because he really has done well and had a great summer academically," said Coach Joe Paterno. "He has been practicing well. I was pulling for him because he was really a positive influence on the squad."
Yisrael, a native of Palatine, Ill., took a redshirt season as a true freshman in 1999, and would have been a redshirt junior this season.
The 5-11, 197-pounder started every game last season at Hero, and was fourth on the squad with 71 tackles, 47 solo, including three minus-yardage plays, with one sack.
Yisrael was second with 10 pass breakups and forced and recovered a fumble. He also had a pick against Ohio State, stopping a drive immediately after Penn State had rallied to take a 29-27 lead. Yisrael made a career-high 11 tackles in the win over Indiana and recorded 10 stops and a fumble recovery in the comeback win at Northwestern.
He was on the field for 902 snaps last season, the second-highest total on the team.
Yisrael was a prep All-American and All-State selection as a wide receiver, defensive back, punter and kickoff returner at Palatine High School in suburban Chicago.
Yisrael is the second Nittany Lion safety lost for the season with a torn ACL. Junior Ben Lago suffered the same injury on Aug. 17.
An article Saturday in the Allegheny (Pa.) Times said Yisrael was awaiting punishment from Paterno after being arrested for driving under the influence last November. He could have been suspended for five games, but indications were that Paterno was going to be lenient.
"You admire kids who pull themselves up by the bootstraps, and I was kind of pulling for him because he's been a positive influence on the squad after he made the one mistake," said Paterno. "I probably would have played him."
The Nittany Lions open their season Aug. 31 at home against the University of Central Florida.