Northern Ireland golfers Graeme McDowell and Gareth Maybin share a four-shot lead going into the final round of the Andalucia Masters.
McDowell, the U.S. Open champion, shot a 1-over 72 and Maybin, ranked 165th in the world, a 1-under 70 to reach 6 under after the third round at Valderrama.
McDowell knew he squandered a good opportunity to go into the fourth round with a big advantage as he seeks his third victory of 2010.
Standing in the middle of the 18th fairway on the course which staged the 1997 Ryder Cup, he was two shots ahead of the field.
However, he misjudged the strength of a crosswind and put his second shot in a greenside bunker. Then he needed four more shots to get the ball in the hole running up a costly double bogey.
''Standing on the fairway I thought about having a comfortable lead and what happened was just careless,'' McDowell said.
''But there was enough good golf out there to make me happy. I am going into the Sunday afternoon with a chance to win a golf tournament and that's where I want to be.''
Just as surprising was the performance of Maybin, who has never won on the European Tour yet found himself in serious contention for the ?500,000 ($700,000) winner's purse.
Beginning his third round two shots behind McDowell, he looked nervous as he opened with two bogeys. But he responded immediately with two successive birdies.
After another birdie at the 10th he played almost textbook golf by finishing a difficult round with nine straight pars.
Maybin believes he could overcome McDowell again in the final round.
''Graeme is probably the hottest golfer in the world at the moment,'' he said. ''So I will take a lot out of going out there and shooting better than he did.''
Conditions were so windy and difficult on Saturday that from 13 players under par at the start of the round, only six were left in red figures at the end.
The frustration certainly got to Niclas Fasth of Sweden, who occupied third place after two rounds only four shots off the lead.
Fasth, a former Ryder Cup player, dropped out of contention with six bogeys in nine holes before losing his temper on the 18th tee.
After the click of a camera shutter as he drove into trees, Fasth stormed into the nearby crowd shouting abuse and branding a club before demanding officials take away the credentials of the offending cameraman.
As Fasth subsided, Ireland's Damien McGrane moved into a share of third place with a 70. Miguel Angel Jimenez shot par to join him at 2 under.
Martin Kaymer, who needs to win or finish second at Valderrama to take Tiger Woods' place at the top of the world rankings, improved in his third round, but his 70 still left him nine shots behind McDowell and Maybin.
