Westwood a doubt for Ryder Cup as injury worsens

And the world No 3 even hinted his participation in the Ryder Cup in October could be in doubt due to the ruptured plantaris muscle in his right calf.

"I will be out for as long as it takes to get right," Westwood told reporters after a second round of 76 left him seven over par at Firestone.

"Hopefully it will be in time for the Ryder Cup."

Westwood suffered the injury at the end of June but still managed to finish a distant second behind stablemate Louis Oosthuizen in the Open at St Andrews.

However, the 37-year-old added: "It just seems to be getting worse. There's no strength in it.

"I don't have a deal of confidence in it, and then on the way down I'm finding it hard to hold my weight on it and then push off."

Asked what he could do to get better, Westwood added: "Sit on my backside for six weeks like they keep telling me. It's the only way to improve it.

"I'd like to be working out and I can't put any weight on it in the gym, so my legs feel weak. That's just it."

Six weeks out would leave Westwood with around two weeks to get ready for the Ryder Cup at Celtic Manor, which starts on October 1.

Westwood won just one point from four matches as Europe lost the trophy at Valhalla in 2008, but has previously been a vital member of the team and captain Colin Montgomerie will be keen to have him on his

12-man team.

The qualifying period ends on August 29 after the Johnnie Walker Championship at Gleneagles, with nine players booking their place on the team automatically and Montgomerie adding three wild cards.

Tiger Woods's hopes of fending off Phil Mickelson's bid to replace him at the top of the world rankings suffered another setback on the second day's play in Ohio.

The American carded an over-par round for the second day running as he slumped to six over par and near to the foot of the leaderboard following a second-round 72.

Mickelson has the chance to depose Woods as world No 1 and can do so with a top-four finish coupled with Woods finishing outside the top 44.