Rory McIlroy won’t be back to defend his title in the Open Championship.

The world’s No. 1 player announced Wednesday that a ruptured ligament in his left ankle will keep him from from playing in the Open Championship at St. Andrews

McIlroy said he injured his ankle while playing soccer with friends in Northern Ireland over the weekend.

He will be the first player not to defend his Open title since Ben Hogan in 1954.

McIlroy says his recovery is going well, but he wants to take a cautious approach. He says he wants to compete only when he is fully healthy. It was not clear how much longer he would be out.

He also is the defending champion at the Bridgestone Invitational and PGA Championship, both over the next five weeks.

McIlroy had been the favorite at St. Andrews at 5-1, but he fell to 8-1 on Monday morning after his injury was announced, according to the Westgate Las Vegas SuperBook. Jordan Spieth, meanwhile, went from 6-1 to 9-2 and is now the betting favorite. The 21-year-old Texan goes to the Open Championship as only the fourth player with a shot at the modern Grand Slam.

“That’s a big blow to the Open if he misses it,” former Ryder Cup captain Sam Torrance said from Wimbledon.

McIlroy won the Open last year at Royal Liverpool by going wire to wire and taking a 6-shot lead into the final round. He also won the PGA Championship, joining Jack Nicklaus, Tiger Woods and Bobby Jones as the only players in the past century with four majors at age 25 or younger.