Westwood, who entered the week with a deficit of more than €127,000, cannot be stopped if he wins the tournament and is on target for a €1.8m pay-day.

On 15 under par following a superb bogey-free 66 he leads by two from fellow Englishman Ross McGowan – he also shot 66 – and by five from not just McIlroy, but also Padraig Harrington and Swede Alexander Noren.

“I got myself in the position I wanted to be in, but after that finish I’ve left myself an uphill task,” said the Northern Ireland golfer, trying to become the youngest number one since Seve Ballesteros in 1976.

“But I’ve still got 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.

“On 16 I got a flyer (it avoided the water over the green by inches, but he failed to get up and down after taking a shoe and sock off and rolling up a trouser leg), on 17 I left myself a tricky two-putt and the last was just a bad third shot.”

After taking a two-stroke halfway lead with a 20-foot closing birdie effort Westwood saved par on the first from almost as far and then rolled in a curling 30-footer only three holes later.

The world number five, who topped the Order of Merit in 2000, had to wait until the ninth for his next birdie, but it was to be the start of three in a row and more were to come on the 15th and 18th, both par fives.

McGowan, who won his first Tour title in Madrid last month after a third-round 60, was in spectacular form again as he went to the turn in 31 and led by two until Westwood hit back.

It looks to have come down to the two of them with German Martin Kaymer and Ross Fisher only two under after rounds of 72 and 70 respectively.

They were in a tie for 37th, but just to have a chance Kaymer had to finish in the top four and Fisher either first or second.