Stuart Manley admitted he was “delighted” after a four under par 68 took him to 11 under at the Portugal Masters and gave him the halfway lead.
The Welshman’s efforts at Oceânico Victoria Golf Course give him a one shot advantage over Alvaro Quiros, with Magnus A Carlsson and Paul Lawrie a stroke further back on nine under.
Manley had led overnight after an opening 65 in which he played his back nine in five under par.
And he again shone in the second half of his round thanks to an eagle at the par five 12th and birdies at the 15th and 16th.
On the way out he had produced a birdie at the second but bogeyed the seventh.
“I played pretty good today. Didn't quite make as many putts as yesterday, but I would definitely have taken 68 at start of the day so delighted,” he said.
Manley is currently 174th on The Order of Merit and needs a good result here to boost his chances of avoiding Qualifying School.
“To be honest, I played pretty good all year, but just not taking it into tournament golf,” he added.
“I played great on a Tuesday and Wednesday, practised really well and then I step on the first tee on the third day and just not quite performing to the way I've been playing on Tuesday. It's just confidence or belief and obviously this week will give me a little bit more belief to go out there and know I'm good enough.”
Manley, who has never been in contention for a Tour title before, added: "I half expected to play average, so I thought I might as well be aggressive.
"I definitely would have taken 68. I know what I've got to do now - I've just got to commit to the shots.
"If they don't come off they don't come off, but as long as I commit that's all I can ask."
Quiros produced a bogey free round of 68 to remain a shot behind the leader.
He picked up a birdie at the first and another at the fifth - a hole he bogeyed yesterday - to reach the turn two under.
For the second consecutive day he birdied both par fives on the back nine, the 12th and the 17th, to complete a four under par round.
“The greens are really good and the fairways are very good,” he said.
“I'm confident with my long game and within my putting, too, so it's not going to be a problem for the weekend. I still have a chance and I'm not the number one player on the weekend, I have to recognise, but I'm hitting the ball well.”
After a 69 yesterday Carlsson made consecutive birdies at the second and third and followed that up with another at the par five fifth.
He picked up another shot at the 509 yard par four seventh to complete a magnificent front nine 32 and his good form continued after the turn with a birdie at the 11th.
And when he picked up a birdie at the par three 13th for the second day running Carlsson had opened up a two shot lead.
Carlsson birdied the short par four 15th but a dropped shot at the next saw him finish with a 66.
He said: “So far I'm really enjoying this, playing good golf, perfect weather. This week, I've been hitting the ball very good off the tee and good iron shots.
“Today is not as hot as yesterday but it's really good. I wish we had more tournaments this time of the year down here.”
Lawrie joined Carlsson on nine under after a bogey free seven under par round of 65.
The Scot birdied the second, the fifth and the eighth on the way out.
After the turn he picked up shots at the tenth, 12th, 14th and 15th.
“I've been playing good for a while,” he said. “But I holed a few putts today which helped. The wind is up a bit and the course is much tougher than yesterday. I played solid, so it wasn't too difficult today.
“It's been disappointing obviously to be 95th on the Order of Merit for me, I'm a better player than that but that's what I am. I've been putting poorly but that's what I've been struggling with. You never realize how hard the game is until you struggle with the putter.”
Grégory Bourdy, Chile’s Felipe Aguilar, Jyoti Randhawa, Robert Karlsson and Jean-François Lucquin are all one shot further back on eight under.
Karlsson - looking to strengthen his lead at the top of The Order of Merit - produced a five under par round with seven birdies and two bogeys, one of which came at the last when his approach landed in the rough to the right of the green.
He still looks set to move closer to the Harry Vardon trophy as his main rival playing this week, Lee Westwood, is three shots behind him.
Karlsson said: “I hit a lot of good shots today and still think I can do better but it was nice to get it going a bit more.”
Bourdy recorded a five under par 67 to go eight under for the halfway stage.
For the second day running the Frenchman produced a bogey free round, with birdies coming at the second and the fifth on the way out.
He birdied the 546 yard par five 12th and then recorded back to back birdies at the 14th and 15th.
He said: “My driving was much better, and the irons were not quite the same as yesterday. I didn't make a lot of birdies during the front nine but then I made some and it's very good.”
Randhawa followed yesterday’s 66 with a two under par 70 which contained six birdies and four bogeys.
In stark contrast to yesterday’s bogey free round, the Indian dropped shots at the first two holes.
He recovered with consecutive birdies at the fourth and fifth and went three under for the day with birdies at the eighth, ninth and tenth.
Dropped shots at the 11th and 14th came either side of a birdie at the 12th before four consecutive pars completed a back nine 36.
For Lucquin there was no repeat of yesterday’s hole in one but he did birdie the eighth - the 168 yard par three where his ace came yesterday.
He also strung together four birdies in a row from the 12th to the 15th but three bogeys left him to sign for a three under par 69.
Aguilar’s second successive 68 started with birdies at the first three holes.
That flying start was steadied by a bogey at the sixth, but another three birdies and a bogey on the back nine leave the South American with a real chance going into the weekend.