Ireland's Graeme McDowell slipped way off the pace in the Johnnie Walker Classic in Phuket, Thailand, after four-over-par second round 76 undid all the good work of his first round 67.
McDowell was just two off the lead after yesterday's round but this morning the Portrush man could manage only one birdie among five bogeys and he now lies 10 shots of the pace being set by England's Oliver Wilson.
Damien McGrane will be around for the weekend after narrowly avoiding the cut thanks to a 72 leaving him on one-under-par for the tournament.
Dubliner Peter Lawrie could only go one better than his first round 75 and misses the cut on five-over-par.
Wilson leapt to the top of the leaderboard at the halfway point after carding a six-under-par 66 at the Blue Canyon Country Club today.
The Mansfield golfer, who finished 31st at the Dubai Desert Classic last month, had two birdies on his front nine but improved dramatically after the turn.
He eagled both the 544-yard 11th and the 586-yard 15th, carding another birdie at the short 14th.
However, even though he spoiled his card with a bogey five at the last he still leads South Africa's Anton Haig — who shot a tournament low 64 — by one with world number eight Retief Goosen and Australian James Nitties a further shot adrift.
"It's nice to be leading the tournament," said the 26-year-old Wilson. "I've just been working on a few mental things this week trying to stay relaxed and enjoy it and it seems to work.
"So if I can keep doing that, you never know, and you never know what will happen on the weekend."
Haig said: "I just kept good composure out there, kept fighting and never gave up. I hit all the par fives in two and really did hit it good out there.
"I hardly missed a fairway, putted really solid. All in all, compared to yesterday, I really hit it a lot better."
Colin Montgomerie carded a two-under-par 70 to move to five under for the tournament alongside Graeme Storm, although fellow English duo Paul Casey and Nick Dougherty both missed the cut.
Casey, who started on the back nine, was level par overall heading down the last but a double-bogey seven at the 561-yard ninth ruined his chances as the Ryder Cup hero carded a 75 for a two-over total.
Dougherty carded a nine-over-par 81 to plummet to five over par after starting the day four under.
Scotland's Steven Gallacher, who began the day tied for second, shot a 76 to drop to two over and out of the tournament.
The 2003 Masters champion Mike Weir (level par) and former Johnnie Walker Classic winners Ernie Els (one under) and Adam Scott (one under) all made the cut.
