Philadelphia 76ers star forward Paul George underwent arthroscopic left knee surgery on Monday after suffering an injury in a recent workout, the NBA team announced.

The 35-year-old American had a successful operation in New York and will begin a rehabilitation program with progress regularly monitored and a re-evaluation prior to the start of training camp in late September.

READ: NBA: Paul George out for season to recover from his injuries

George, a nine-time NBA All-Star, was signed by the Sixers last July after stints with Indiana, Oklahoma City and the Los Angeles Clippers.

Philadelphia, which has not gone past the second round of the playoffs since losing to the Los Angeles Lakers in the 2001 NBA Finals, was expected to contend for the crown with George joining star center Joel Embiid and guard Tyrese Maxey on a four-year deal worth $212 million.

But the 76ers went 24-58, their worst record since 2015-16, and missed the playoffs.

George was nagged by multiple injuries including a knee bone bruise and adductor issues and was benched for the season on March 17 with knee injuries, averaging 16.2 points, 5.3 rebounds and 4.3 assists in 41 games, half a season.

Embiid played in only 19 games due to injuries and the star trio with George and Maxey was only on the court together in 15 contests.

Over a 15-season NBA career, George has averaged 20.6 points, 6.3 rebounds, 3.7 assists and 1.7 steals a game.