Singh has won his last two events, including the Canadian Open

The 41-year-old Fijian broke Tiger Woods' grip on the top spot after a head-to-head duel earlier this month.

Singh, who has seven wins this year, is now only a second-place finish this weekend away from beating Woods' single season earnings record.

Woods is missing the Pennsylvannia event after his Ryder Cup exertions.

"I'm enjoying the ride right now," Singh said.

"I'm feeling really confident in my game. I'm really looking forward to going out there and performing well again."

Woods' cash mark

Woods, who had been atop the rankings for more than five years, explained his absence, saying: "I didn't think I was going to be ready physically and mentally.

"The Ryder Cup took a lot out of me emotionally, and I didn't think I would be ready."

Singh is more than $3m clear of second-placed Phil Mickelson, who is also absent, on the PGA Tour money list.

The $810,000 he won two weeks at the Canadian Open upped his season earnings to slightly less than $8.7m, or $488,755 less than Woods' record of $9.1m set in 2000.

"I've still got five events in the US - two of them no-cut events," Singh said recently.

I'm glad I'm here - I'm glad I'm playing David Toms US Ryder Cup player

"I'm not going to back off. I'm going to try to come out and win a few more events by the end of the year."

Singh hopes to make this his 23rd career title and follow a tradition of 40-plus winners here that includes 2002 winner Dan Forsman and defending champion J.L. Lewis.

Last year, Lewis set the tournament 72-hole record with a 22-under-par 266, eclipsing Australian Robert Allenby's 269 from 2001.

While Woods and Mickelson are absent, US Ryder Cup players Stewart Cink, Chris DiMarco and David Toms did summon the strength to compete this week. DiMarco won here in 2000.

"The Ryder Cup takes a lot out of you mentally and physically," Toms said. "So it's tough to come back and refocus.