Festus Ezeli is in his fifth NBA season. (AP)

Portland Trail Blazers center Festus Ezeli will likely undergo season-ending surgery on his left knee, league sources told The Vertical.

Ezeli’s representatives at BDA Sports and the Trail Blazers have not yet finalized the surgery, but he’s strongly leaning toward the procedure, sources said.

Ezeli had been contemplating surgery in recent weeks due to an ailing left knee that has failed to adequately respond in rehab, sources said. There has been significant consultation with the Blazers’ medical staff and knee specialists on the necessity for the procedure, sources said.

Portland (13-15) had hoped Ezeli could play a part in anchoring a defense that has slipped to 28th in the league in points allowed. The Blazers have struggled to defend the paint this season.

After three seasons with the Golden State Warriors, Ezeli signed a two-year, $15 million contract with the Blazers.

The deal is partially guaranteed in 2017-18 for $1 million out of his $7.7 million salary, which means he could have value to the Blazers as a contract to include in a larger trade.

Portland has until Jan. 15 to apply for a Disabled Player Exception worth $3.7 million if Ezeli misses the season. To use the exception, the team would need to create a roster spot. The Blazers are currently $27,000 below the luxury tax and have guard Tim Quarterman on a non-guaranteed deal.

As the 30th overall pick in the 2012 NBA draft, Ezeli developed into a solid backup center in Golden State. Ezeli averaged seven points and 5.6 rebounds in 46 games last season.

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