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Mickelson reveals injury struggle

Phil Mickelson could replace Tiger Woods as world No. 1 this weekend © Getty Images

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Phil Mickelson has admitted he is only playing at 90% after he revealed that he has been struggling with arthritis for two months.

The world No. 2 claims the problems started shortly before the US Open in June, and was the pain was so intence he was unable to walk.

Mickelson has been injecting himself on a weekly basis in an attempt to stave off the painful stiffness of the psoriatic arthritis.

"I woke up and had intense pain in some joints and tendons, so much so that I couldn't walk," he said. "It progressively got worse, so I got it checked out."

"Then it started getting worse into other joints, the hips and ankle and elbows and shoulders. That's when I got concerned.

"It was a little bit concerning, but I've had some great doctors and things have been looking great and long-term there shouldn't be any issues.

"The treatment is a thing called Enbrel. I give myself a shot a week and it lowers my immune system and stops it from attacking the joints. It's very treatable and the medicine I've been taking has been very helpful. I feel 90%."

Mickelson was on anti-inflammatories at the Open Championship last month, and could only manage 48th at St Andrews. With the world No.1 spot firmly in his sights, Mickelson shot a final round 78at the Bridgestone Invitational to miss out on the chance to overtake Tiger Woods at the top of the world rankings.

"Heading into the PGA I'm probably not as sharp as I would like to be," he admitted. "I didn't play well at the British obviously, I didn't play well last weekend, but I believe that the game's coming around."

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