CRANS MONTANA, Switzerland -- Teenager Rory McIlroy shot a 5-under 66 Saturday to take a four-stroke lead after the third round of the Omega European Masters.

The 19-year-old player from Northern Ireland had a 54-hole total of 13-under 200 to lead a group of six players bunched on 204 in the European Tour event. That group included Robert Dinwiddie, who shot the low round of 64.

Defending champion Brett Rumford, who shared the overnight lead with McIlroy, shot 73 and dropped seven shots behind the leader.

McIlroy, who totally outplayed Rumford, would become the third-youngest winner in European Tour history if he can close out the victory on Sunday.

South African Dale Hayes was only 18 when he won the 1971 Spanish Open, while Seve Ballesteros was just five days younger than McIlroy at the 1976 Dutch Open -- the first of his record 50 Tour victories.

Rumford, tied for the lead at halfway with the Northern Ireland teenager, threw down the gauntlet with an opening 40-foot eagle putt. But McIlroy had already hit his approach to the par-5 first to three feet, made the putt for a matching 3 and by adding six birdies.

That took last year's leading amateur at the British Open, who began his first trip to Crans-sur-Sierre with a 63, to 13 under par and continued a remarkable turnaround in his fortunes after missing the last three halfway cuts.

His closest challengers now, all on 9 under, are England's Dinwiddie, Frenchmen Christian Cevaer and Jean-Francois Lucquin, Spaniard Alejandro Canizares, Argentina's Juan Abbate and also Julien Clement, a Swiss player who does not have a European Tour card and is ranked 779th in the world.

McIlroy's professional career is still not quite one year old. He left the amateur ranks after winning a Walker Cup cap and within a month had finished third in the Dunhill Links at St. Andrews and fourth at the Madrid Open.

As a result, he did not have to go to the European Tour qualifying school, but until this week his 2008 campaign had not delivered in the way many people expected. He is 89th on the Order of Merit, only six places higher than he managed in four starts last year. But winning on Sunday could more than double his money and put him 33rd.

McIlroy did, however, have a wobbly spell after turning in 32, his lead being cut to only one when he bogeyed the 10th and 12th. McIlroy badly needed a good shot to settle him back down and it came when his tee shot to the 200-yard next to three feet.

Two putts on the long 15th brought him another birdie and he pitched close at the 388-yard 17th for his last of the day.

"That settled my nerves," said McIlroy, who for his eagle on the 543-yard first needed only a drive and 9-iron in the thin air. "It was definitely more satisfying than the 63 given the circumstances. Brett is a very good player and 5 under was a very good effort.

"This is my first time in this situation and I'm just really looking forward to tomorrow," he added. "I don't want to take my foot off the pedal.

"I've a four-shot lead and I'd like a six-shot lead tomorrow," he said. "Trying to make birdies is the way I play my best. It would be fantastic to win."

Clement is the surprise name on the leaderboard, but Dinwiddie's presence there is remarkable, too. He began the tournament with a 5-over 76 that had him way down in a tie for 140th spot, but he has since added back-to-back 64s and now has another chance to win in his rookie season on Tour.

Rumford dropped all the way to 16th, seven shots adrift, and it will take something remarkable for him to become the first player to make a successful defense of the title since Ballesteros in 1978.

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