By Andrew Porter

PHILADELPHIA (CBS) — Joel Embiid could miss two more games with back stiffness, according to ESPN’s Adrian Wojnarowski.

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Woj reports that “there is optimism” Embiid is able to return for the Sixers’ Christmas Day matchup at Madison Square Garden against the Knicks.

After playing 48 minutes in a triple-overtime loss to the Thunder last Friday, Embiid missed Monday’s game at Chicago and Tuesday’s game vs. the Kings at home with back stiffness. The Sixers lost both of those games and have now dropped seven of their last eight games, falling to 14-16.

Embiid signed a five-year maximum contract extension worth $146.5 million in October. He is averaging 24.1 points, 11.0 rebounds, and 3.5 assists per game this season.