Ballard has "multiple facial fractures, a concussion and is out indefinitely," the team said.
After passing the puck near center ice, Ballard turned to avoid the hit and his head hit the glass and the ice. He remained on the ice for several minutes before walking to the locker room. The Wild announced he was conscious on his way to the hospital.
Martin was not penalized for the hit during the game, and Michael Russo of the Minneapolis Star-Tribune reports he will not face discipline from the league.
Ballard, 32, is in his second season with the Wild and has one assist and 26 penalty minutes in 14 games this season.
Wild defenseman Nate Prosser said he would pray for Ballard after the hit.
Prosser was yelling at the Islanders bench after the hit. Speaking to reporters in the locker room after the game, Prosser had to stop to compose himself a couple of times.
"That's something we never want to see in this sport," Prosser said.
Minnesota is 15-10-1 and in fifth place in the Central Division.
- Paul Palladino