-10 P Harrington (Ire) -7 T Woods (US) -5 T Clark (SA) J Kelly (US) Selected others: -4 O Wilson (Eng), MA Jimenez (Spa), S Cink (US), K Perry (US), A Cabrera (Arg) -3 G Ogilvy (Aus) -2 I Poulter (Eng)
Harrington maintained his place at the top of the leaderboard
Padraig Harrington shot a three under par 67 to extend his lead after three rounds of the World Golf Championship at the Firestone Country Club.
The Irishman secured an overnight three-shot lead at 10 under par overall with world number one Tiger Woods in second place on seven under.
It was a superb third-round five under which put Woods back into contention.
Meanwhile, England's Oliver Wilson was tied in fifth after a round of two under left him six shots off the lead.
South African Tim Clark and American Jerry Kelly finished the day five shots off Harrington going into the final round.
Woods and defending champion Harrington will play together in the first two rounds of the USPGA Championship at Hazeltine National in Minnesota, which begins on Thursday, but Sunday's fourth round in Ohio should make for an intriguing appetiser.
"I do feel comfortable here," said Woods, who birdied holes 13, 15, 16 and 18 to finish his round in style.
"As of right now, I'm tied for the lead but more than likely I'll probably be one or two back going into tomorrow.
"This golf course, you've got to be very patient."
Harrington was not intimidated by Woods' late charge and made one of his own with back-to-back birdies, rolling in a 30-foot putt at the 12th and another of 21 feet at the 13th to pull two strokes clear.
The Dubliner birdied the 15th to take a three shot lead and even after he made a careless bogey on the 16th, he answered with a 20-foot birdie on the 17th to restore his three-shot lead.
"I'm obviously happy with my day's work," said Harrington after his third round.
At the end of the day there's probably never enough room between you and Tiger, so I know I have to play well on Sunday if I'm going to win
"The key is to keep breaking 70 and make sure if anyone else is going to win this tournament they're going to have to play well."
Despite the three-shot cushion though, Harrington knows he will have to be at his best to defeat Woods on Sunday.
"I realise I'm going to have a difficult day, that's for sure," he said.
"This golf course has obviously been very good for Tiger, he's played well here in the past and done well so I don't think anything is going to be easy."
He added: "I was trying to put as much room between me and the field.
"But at the end of the day there's probably never enough room between you and Tiger, so I know I have to play well on Sunday if I'm going to win."