HSBC Champions, Shanghai, 4-7 November
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Phil Mickelson says he is reacting well to treatment for arthritis as his bid for the number one ranking resumes at this week's HSBC Champions event.
The 40-year-old has been suffering from psoriatic arthritis since before June's US Open and his best result since was a tie for eighth at the BMW Championship.
"I've had good time off. I'm on a good medicine. Things feel pretty good," said the American world number four.
"I've been taking one drug and I feel 100%. I cannot believe the difference."
Mickelson revealed in August that had been coping with the condition since the week prior to the US Open and his results appear to have suffered at a consequence.
He missed the cut at The Barclays, came joint-25th at the Deutsche Bank Championship, eighth at the BMW Championship and 22nd at the Tour Championship.
"The US Open, I might have been affected," said Mickelson, who has never reached world number one and missed 12 chances to replace Woods as number one this year.
"But I'm excited where I'm at, excited I can work out the same and get back into the gym, and get back to work again."
Mickelson, whose wife and mother were diagnosed with breast cancer in 2009, said the problem surfaced just before the US Open.
He woke up with intense pain in his tendons and joints and despite getting through the event with stretching and anti-inflammatories, the problem worsened.
Mickelson started taking his medication around the time of the USPGA Championship in August and said it took a full eight weeks for it to kick in.
That would have been a week after the Ryder Cup, where he defeated Peter Hanson in the singles.
"I feel terrific," said the left-hander. "I've been able to do all the normal activities in my life. I've been able to practice at whatever level, and I honestly don't feel any different than I did before."
Mickelson's attention now shifts to Shanghai, where he is the defending champion and has been paired with England's Lee Westwood for the opening round.
On Sunday, Westwood ended Tiger Woods's 281-week reign as world number one but the mantle could again switch hands at the Sheshan International Golf Course.
Westwood has a narrow lead over Woods and PGA champion Martin Kaymer, with Mickelson in fourth.
Mickelson is likely to need at least a fourth-place finish to be in with a chance of clinching top spot, depending on how his rivals fare.
When asked if it was frustrating to see the number one ranking fall into someone else's hands after all the time he spent at number two behind Woods, Mickelson had no complaints.
"I haven't played well since the Masters, or as well as I expected maybe since the US Open," he said.
"So I don't feel like I've earned it. I've got to play well and win more tournaments and then I feel like those results will take care of itself."
After Shanghai, Mickleson finishes his season at next week's Singapore Open before starting up again in in January.
Potenshöjande medel - potenshöjande medel