(CNN) -- Lee Westwood will take a commanding five-shot lead over European Tour money list rival Rory McIlroy into the final round of the season-ending Dubai World Championship on Sunday.
The Englishman carded a six-under-par 66 in his third round on Saturday to take the tournament lead by two shots from compatriot Ross McGowan, while Race To Dubai leader McIlroy suffered a nightmare finish.
The 20-year-old Northern Irishman had been just a shot behind his 36-year-old rival, but bogeyed the last three holes of the Greg Norman-designed Jumeira Earth Course's "Golden Mile" closing stretch to card 69.
He was left on 10-under 206 alongside three-time major winner Padraig Harrington (69) and Sweden's Alexander Noren (67).
Westwood, on the other hand, had a blemish-free round which he crowned with a birdie at the par-five 18th to put himself in pole position to win what used to be called the Order of Merit for the second time.
He also triumphed in 2000 when he overhauled Darren Clarke -- another Northern Irishman -- in the final week.
Westwood, who led by two shots at the halfway stage, stands to earn $1.25 million for winning the tournament plus a bumper jackpot for claiming the Race To Dubai title.
"I've had the highs, I've had the lows, and I am back on a high. I'm enjoying it," Westwood, who fell outside the world's top 250 in 2002, told reporters.
"This is as good as I feel like I've swung it almost all year and when I was winning a lot -- in the last century! -- I had this kind of attitude.
"I would not be outwardly cocky, but I am just being more confident. I've had 30 wins and I think I've finished tournaments off more than anybody else on the leaderboard. I don't mind putting myself up there to be shot at. You back your ability."
McIlroy, seeking to become the youngest European No. 1 since Seve Ballesteros in 1976, briefly joined Westwood at the top with birdies at 14 and 15, but had to putt with his feet in the water at 16, three-putted at the short 17th and hit a water hazard at the last.
"I got myself in the position I wanted to be in. After that finish I've left myself an uphill task," he said.
"But I've still got a shot a shot to win this -- I feel a low round is in me and I feel it's necessary. The guys ahead of me are playing well."
Martin Kaymer and Ross Fisher, the two other players who had gone into the tournament with a hope of toppling McIlroy, were well out of contention after ending the third round in a tie for 36th on two under.
Germany's Fisher, who needed to finish in the top four, carded a 72, while Englishman Fisher -- who requires victory to win overall -- shot 70.