Nonito Donaire's move up to featherweight on Saturday night in Corpus Christi, Texas resulted in a ninth-round knockout of Vic Darchinyan in a rematch of Donaire's much more dominant fifth-round knockout in their 2007 flyweight title fight.

Donaire, coming off a decision loss to Guillermo Rigondeaux in their April junior featherweight unification fight, didn't look like the fast and explosive fighter we have all become used to seeing. In fact, before the knockout, Donaire was trailing on two scorecards and was even on the third.

One of the reasons, perhaps, for his lackluster performance was an injury -- a possible cheek fracture -- suffered early in the bout.

Donaire is due to have an MRI on the injury on Tuesday afternoon in Las Vegas, manager Cameron Dunkin told ESPN.com.

Dunkin said that Donaire went to the hospital to be examined after the fight and got an X-ray "that showed maybe a hairline fracture, but not a significant one. We think it will heal, as opposed to Nonito needing surgery. So it may be fine. We're thinking it will be fine. But he'll have the MRI on Tuesday to be sure what is wrong."

During his postfight interview with HBO's Max Kellerman, Donaire (32-2, 21 KOs) said he thought he suffered a broken cheek during the fight.

"After the fight, he said he was not in any real pain, but he was uncomfortable," Dunkin said. "It happened when he got hit with a looping overhand left in the third or fourth round."

If Donaire’s cheek is OK, he could be back in action as soon as Jan. 25 on an HBO card in New York, possibly to challenge featherweight titlist Nicholas Walters (23-0, 19 KOs), who recorded his first title defense on the undercard by knocking out Alberto Garza in the fourth round.