Matt Kuchar is fifth on the Ryder Cup points list.

Matt Kuchar withdraws with bad back, adding to mounting list of U.S. injuries

Matt Kuchar withdrew from the PGA Championship just before his tee time on Thursday, giving U.S. Ryder Cup Captain Tom Watson one more worry.

Kuchar, who is ranked No. 6 in the world, cited a bad back when he informed PGA Championship officials that he was withdrawing from the field. Alternate John Huh took his place.

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One of five players already with a spot on the Ryder Cup team locked up, Kuchar is now the third major player that Watson has to worry about with injury.

Kuchar ranks fifth on the U.S. Ryder Cup points list. Jason Dufner, who currently ranks eighth and would make it if he stays inside the top nine, has been hampered by a neck injury in recent weeks.

Dufner didn’t practice this week at Valhalla, but is expected to play because he wants to make some points to stay on the team.

"I'm not going to qualify if I don't make some points this week,” Dufner said. “I seriously doubt I would be a captain's selection with an injury if I didn't play. So I kind of need to suck it up and make some points and try and get healthy.

“I think if I were to make the team after this week, I think I could be healthy by the time the Ryder Cup rolls around.”

And, of course, the biggest injury of them all is Tiger Woods' back. He missed most of the season after back surgery and then withdrew midway through the final round of the WGC-Bridgestone Invitational last weekend. He is playing at Valhalla but is likely going to need to be a captain’s pick in order to make the team.

“You never know what’s going to happen in the next few weeks,” Watson said. “I can’t answer (injury questions) because you just never know.”

Kuchar had been playing well in recent weeks. He was fourth in the RBC Canadian Open two weeks ago and then 12th last week at Bridgestone.

The Ryder Cup begins on Sept. 27.