Penguins star Evgeni Malkin out indefinitely after right knee surgery

June 4 (UPI) -- Pittsburgh Penguins star center Evgeni Malkin will be out indefinitely after undergoing surgery on his right knee.

The Penguins announced the procedure Friday, but the team didn't provide specifics on when Malkin had the surgery or the nature of the operation.

Pittsburgh said Malkin is expected to be unavailable for training camp in September. The team will have a more definitive time frame for his return at that time.

Malkin suffered the knee injury in a collision during a game against the Boston Bruins on March 16. He was forced to miss seven weeks before returning for the final four games of the regular season.

The 34-year-old Malkin aggravated the ailment before the Penguins' first-round playoff series against the New York Islanders. He sat out Games 1 and 2 against the Islanders, but he managed to finish with a goal and four assists in four games during Pittsburgh's first-round postseason exit.

Malkin recorded eight goals and 20 assists in 33 regular-season games for the Penguins, who captured the East Division title. The four-time NHL All-Star selection and 2012 Hart Trophy winner is entering the final year of his contract.

Earlier this week, Penguins general manager Ron Hextall indicated he has no plans to move on from the team's core of Sidney Crosby, Kris Letang and Malkin.