Brooks Koepka says he is "heartbroken" that one of his tee shots at the Ryder Cup on Friday resulted in a spectator losing the sight in her right eye.
The American's drive on the par-four sixth hole veered off course and struck Corine Remande, 49, who had travelled from Egypt to watch the event.
"I was deeply hurt and saddened by the tragic accident," he tweeted.
"I have made contact with her family to offer my sincere and heartfelt sympathy."
Brooks Koepka tweeted his statement on Tuesday
He added: "I am heartbroken by the incident. My thoughts remain with Ms. Remande and her family, and I have asked to be kept informed on her condition."
The 28-year-old golfer, playing at his second Ryder Cup, went over to the Frenchwoman to check on her condition after the incident.
In an earlier interview with AFP, Mrs Remande said she downplayed the incident at the time so the golfer "would stay concentrated".
She added: "It happened so fast, I didn't feel any pain when I was hit.
"I didn't feel like the ball had struck my eye and then I felt the blood start to pour. The scan on Friday confirmed a fracture of the right eye-socket and an explosion of the eyeball."
A Ryder Cup spokesperson told the BBC that the tournament organisers had been in communication with her family and that they would "continue to offer support for as long as necessary".