Alvaro Quiros set himself up for a unique Dubai double when the reigning Desert Classic Champion opened up a four-shot lead on top of the leaderboard at the halfway stage of the $7.5 million Dubai World Championship.
A course-record eight-under par 64, capped by a brilliant eagle on the final hole of the day, gave the popular Spaniard a two-day total of 12-under par 132.
Overnight leader Peter Hanson could only follow his opening-round 64 with a sedate 72 and was four shots off the pace.
Northern Ireland's Rory McIlroy, involved in a thrilling battle for the European Tour's Race to Dubai honour, made successive bogeys on his final two holes to drop down to tied third place at seven-under par 137 along with England's Robert Rock.
Needing to win the tournament to have any chance of becoming Europe's new No. 1, McIlroy, who later revealed he was suffering from a mild case of dengue fever which caused him recent exhaustion and a skewed blood count, is now five behind the leader.
The news was much better for Luke Donald, who could become the only player to win the Money List both on the US PGA Tour and the European Tour on Sunday, as he closed with three consecutive birdies in a round of four-under par 68, which elevated him to tied 12th place on the leaderboard.
The World No. 1 Englishman needs to finish in the top nine to win the Race to Dubai and cap what has been a brilliant season for him.
But the spotlight was on Quiros, and he was intent on spoiling the party for McIlroy and Donald by denying them the pleasure of winning the tournament as well.
"Luke and Rory are not the only two players in this tournament," he said. "Obviously, they are fighting for the Race to Dubai final top position, but the rest of us are playing here to try to ruin the party and this is good - I think otherwise the competition wouldn't be as stiff."
After holing a 20-footer eagle putt on the monstrous 620-yard, par-5 18th, Quiros said: "Hopefully there is even better golf to come. I always seem to do well in the Middle East - the weather is great for one thing and the set up of the courses really suits my game.
"But this is only the half way stage and while it is a good thing for me, there is still a lot of golf to be played."
McIlroy was understandably disappointed with his finish, but he was not giving up on his chances.
"I thought I played solid and standing on the 17th tee, I wanted to pick up another shot and get to 10-under for the two rounds. That would have been perfect but it wasn't to be," said McIlroy, who will be visiting the doctor again Saturday to get an opinion on whether he needs to rest and pull out of the Asian Tour season-ending championship next week.
"I have given myself a bit of an uphill battle but I can make up the shots - I just have to bide my time and play as well as I can."
Donald was elated with his finish and said: "I was frustrated out there. I tried to stay as patient as I can. I tried to just go out there and enjoy it and know that it's just a game, but it's tough. There's a lot at stake, and I want to do my best and obviously try to finish off what I came here to do.
"But yeah, to make three birdies in a row will make the lunch taste great, and hopefully make the next two days a little easier."
"I'm going to need to be even more patient on the weekend. And I need to try and get rid of those silly mistakes. If I can go back to the kind of golf that got me here in the first place, then I should be fine."