Johan Edfors carded an eight under par 64 to establish a two shot lead midway through the second round of the Open de España.
The Swede stormed out of the blocks with five birdies in his first seven holes and after a single bogey added four more on the way in to reach ten under at the halfway stage.
That was enough to overhaul overnight leader Ricardo Gonzalez - who was amongst the day's later starters having shot a first round 67 - while England's Danny Willett returned to a happy hunting ground in Seville with a second successive 68.
The 22 year old vicar's son from Sheffield reached halfway on eight under par - two years after the then world number one amateur played at the Real Club de Golf course and in only his second European Tour start fired a third round 64.
"I think I got to about ten under that day, but the cameras then came and I got a bit scared," he said. "Now it's just a sign that you are doing well."
On his own admission the former Walker Cup player - he was a teammate of Rory McIlroy in 2007 - did not play well in Wednesday's pro-am.
But he now believes it was a blessing in disguise.
"I saw the brutality of the rough and realised you really can't go in it, so I'm not hitting as many drivers as I usually do."
After only 11 putts in a back nine 35 he had four birdies and a bogey in his last six holes, hitting a nine iron to four feet on the eighth and two-putting the long ninth.
Edfors, whose three European Tour wins all came in 2006 as a Qualifying School graduate, was five adrift of Argentina's Gonzalez at only two under overnight.
Gonzalez, yet to resume, was down into a tie for fourth with Edfors' fellow countryman Mikael Lundberg and also Belgian Nicolas Colsaerts and Spaniard Carlos Del Moral.
Edfors doubled his lead to two when he struck a three iron to four feet on the short seventh and made his ninth birdie of the day.
Two closing pars for a best-of-the-week 64 made him ten under, with Willett joined in second place by Frenchman Raphaël Jacquelin when he birdied the last two for a 67.
"I probably aimed a little bit too high after my three wins in 2006," admitted the 34 year old Edfors, who had knee surgery at the start of February.