Peter Hedblom carded a seven under par 64 to open up a one stroke halfway lead at the CASTELLÓ MASTERS Costa Azahar in Spain.
The Swede carded six birdies, an eagle and a single bogey at Club de Campo del Mediterráneo to reach nine under and establish a narrow advantage over Spain's Gonzalo Fernandez-Castaño, Italian Matteo Manassero and Scotland's Paul Lawrie.
Hedblom had three birdies on the way out and was on course for a spectacular finish when he picked up five shots in as many holes from the fourth.
But at the ninth - his last - the three-time European Tour winner found trouble off the tee and ran up a bogey five.
"I think the longest par putt I had today was a tap-in," said the 40 year old. "Everything was going close and then one bad tee shot on the last. Still, in the lead with two days to go."
Hedblom admits this has been something of a frustrating season - he is currently 98th on The Race to Dubai, which would represent his lowest position since 2002.
But he is optimistic that a good finish in Valencia can reignite his chances of reaching next month's Dubai World Championship.
"The game hasn't been as solid as it usually is," he said. "Putting, my lines haven't been as good as they usually are but a good finish here and it can be a good year. Two more rounds like that and I'll be smiling alot."
In near-perfect conditions Fernandez-Castaño took the opportunity to shine on home soil with a five under par 66.
The 30 year old from Madrid picked up three shots on his outward nine holes after starting at the tenth before birdieing the par five fourth and then converting from 30 feet at the ninth, his last.
Afterwards the former British Masters insisted his recent problems with the putter are behind him.
"At the moment, believe it or not, I'm quite confident with my putter," he said. "I can see the ball rolling where I want it so it's good.
""I'm playing well, I'm playing steady golf. Only one bogey on the first two rounds which is a bit of a surprise for me. Normally my rounds are a bit of a rollercoaster!
"But I hope to keep it that way for the weekend. I think I need to improve my wedge game if I'm going to win so that's what I'm going to do this afternoon."
Lawrie had been the joint first round leader with Ricardo Gonzalez, and the former Open Championship winner recovered from three early bogeys to record a one under 70
Teenage sensation Manassero continued his remarkable rise to prominence with a composed round of 66, including a birdie at the 13th when he hit his approach to three feet.
There were mixed fortunes for two stars returning to European Tour action.
José Maria Olazábal showed no signs of the health problems that have kept him off the course for most of the last year as he made the halfway cut with a three under par 68.
But Sergio Garcia struggled with his putter after a two-month break from the game and failed to make the weekend at the course where his father is the club professional following a 73.