Jozy Altidore has left the Americans' World Cup opener against Ghana after appearing to hurt his left hamstring in the 21st minute.

The 24-year-old forward was running down a ball with Ghana's John Boye on Monday night when he lowered his head to attempt to control it, grabbed the back of his left leg and fell to the ground.

Wincing in pain, Altidore was taken off on a stretcher and replaced two minutes later by Aron Johannsson.