NEW YORK >> Braves outfielder Jason Heyward sustained two jaw fractures when he was struck by a pitch and will undergo surgery on Thursday.

The Braves said that Heyward’s jaw has been stabilized, and he was to return to Atlanta on Wednesday night in advance of the operation. The team will announce how long Heyward will be sidelined after surgery is completed.

Heyward was beaned by a 90 mph fastball from New York Mets left-hander Jonathon Niese in the sixth inning of the Braves’ 4-1, 10-inning win on Wednesday. The impact made a loud noise, and the crowd groaned as Heyward crumpled to the ground.

He stayed down on his back for about three minutes before getting helped to his feet. Heyward walked slowly off the field under his own power, escorted by a trainer, and was replaced by Jordan Schafer.

Visibly concerned, Niese tapped himself with his glove as Heyward walked off, and Heyward appeared to acknowledge him.

An inning later, the Mets announced that Heyward was examined by their doctors before he was taken to the hospital for X-rays.

On a tear at the plate since moving into the leadoff spot last month, Heyward began the day batting .254 with 13 homers and 37 RBIs. Atlanta entered with a 15-game lead in the NL East.