Gilas Pilipinas' thrilling 95-88 victory over Saudi Arabia in the quarterfinal qualification came at a cost, as CJ Perez sustained what appeared to be an ankle injury.

The national team’s backup guard hurt his ankle just 70 seconds after checking into the game following a scramble for a loose ball at the 5:52 mark of the second quarter.

Television replays showed a Saudi Arabian player losing his balance and falling onto Perez’s ankle, causing it to twist awkwardly. The veteran guard immediately clutched his right foot and grimaced in pain.

He had to be helped off the court and was taken to the hospital shortly after, according to head coach Tim Cone.

"The only bad part of all of this is the injury to CJ. Looks like a bad injury. He is in the hospital right now. We don't know the extent of it but it did not look good," said Cone who had to make do with the 10 remaining players on his bench.

"I'm not going to pretend to be a doctor and tell you what it is but it was not a good injury so our prayers are with him," added the veteran coach.

Gilas is keeping its fingers crossed that Perez did not sustain a serious injury, especially with the Nationals already missing Calvin Oftana against Saudi Arabia.

The TNT forward was sidelined after tweaking his ankle in the previous game against Iraq and did not suit up against Saudi Arabia.

Fortunately for Gilas, Kevin Quiambao stepped up big in the absence of both Perez and Oftana, firing 17 points, including two crucial three-pointers in overtime.

Dwight Ramos added 13 points and 10 rebounds, while AJ Edu contributed a double-double with 17 points and 11 boards to support Justin Brownlee, who led the way with 29 points -- none bigger than the clutch triple he nailed with 3.7 seconds left in regulation to force overtime.

Still, the growing list of injuries is becoming a serious concern for Gilas as the Nationals head into the quarterfinal showdown against defending champion Australia.