ORLANDO, Fla. — Vijay Singh, golf's version of a workaholic, makes his home on the range.

It is easy to find where he has been by looking for trenches that are 6 feet long and wide as the blade of a 5-iron from pounding balls for hours at a time, even if it happens to be Christmas Day.

He could not recall the last time he went so long without practice.

Then again, he couldn't remember ever being so sick that he could see the outline of his ribs.

Singh played the Johnnie Walker Classic in India two weeks ago, returned home to Florida and spent the next four days afraid to stray too far from the bathroom. He caught the flu and a stomach virus, a nasty combination that caused him to drop 18 pounds in less than a week. It was so bad that he nearly withdrew from the Arnold Palmer Invitational.

"Tried to eat clean and drink bottled water, and it didn't work," Singh said Friday after building a two-shot lead at Bay Hill. "I got the flu and a stomach virus, so both things were not very good. I came back on Monday and just never left the bathroom for four days. It was almost a forced rest."

The recovery has been nothing short of sensational.

One week after he finally felt strong enough to hit balls, Singh found himself atop the leaderboard going into the weekend at Bay Hill, where he is trying to become the first back-to-back winner since Tiger Woods.

Woods, however, looked sick every time he walked off the green.

Trying to build on a winning streak that dates to September, Woods has been frustrated by the speed of the shoddy greens and left several putts short. The result was a 68, which left him seven shots out of the lead and in a tie for 20th, a 36-hole deficit he hasn't faced since the British Open last summer.