Serge Ibaka's four-year contract extension with the Oklahoma City Thunder is for $49 million guaranteed and could be worth up to $51.5 million, according to HoopsHype.com.

Ibaka's four-year deal reach even higher than the originally reported $48 million value if certain team and individual goals are met.

The Thunder are looking to lock up the core of their team for the long-term and have successfully done so with three of their top four players with Ibaka, Russel Westbrook and Kevin Durant now signed long-term. The only player missing is James Harden, whom the Thunder have stated they are working hard to extend as well. Harden is scheduled to be a restricted free agent after the expiration of his rookie contract next summer.

Ibaka, at just 23 years old, has turned into one of the elite defensive players in the NBA in his four seasons with the Thunder and average 9.1 points, 7.5 rebounds and 3.7 blocks per game last season.

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