The NBA club didn't reveal the terms of its deal with the rookie forward, who it obtained from Sacramento in a draft-day trade.
Pendergraph, the 31st pick overall in the 2009 draft, needs the operation to correct a left hip impingement. It's not known when he will be ready to play.
Pendergraph averaged 12.6 points and 7.5 rebounds in four seasons at Arizona State.
2014: The Year in Music [PHOTOS]