Los Angeles Clippers star Blake Griffin will undergo minor surgery on his right knee and is expected to return at some point in January, league sources told The Vertical.

Griffin will undergo the procedure, considered a “clean up,” early this week, league sources said. Recently, Griffin has also struggled with left calf and knee soreness. Griffin played 38 minutes in the Clippers’ loss to the Washington Wizards on Sunday, posting 26 points, seven rebounds and seven assists.

Griffin is off to a stellar start to the season for the Clippers, averaging 21.2 points, 8.8 rebounds and 4.7 assists per game. The Clippers currently have a 20-8 record, and Griffin’s loss is a significant blow to coach Doc Rivers’ rotation, which will now need to rely upon forwards Marreese Speights, Wesley Johnson and Brandon Bass to play more integral roles.

Griffin played in 35 games a season ago after suffering a fractured hand in a fight with a member of the Clippers’ equipment staff in January. Despite Griffin’s return in April and their 2-0 lead over the Portland Trail Blazers in the first round of the Western Conference playoffs, the Clippers lost Griffin and Chris Paul to season-ending injuries in Game 4 and lost the series in six games.

Griffin had surgery on his right knee in his freshman season at Oklahoma in 2008 and had a procedure for a fractured left kneecap as a rookie with the Clippers in 2010.

Griffin has averaged 21.4 points, 9.5 rebounds and 4.1 assists in seven NBA seasons.

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