Graeme Storm let a five-shot advantage leak away and will embark on tomorrow's final round of the KLM Open in a four-man tie at the top of the leaderboard.
The 34-year-old Englishman had negotiated his first two rounds and the first 12 holes of his third without dropping a shot, and at 14 under he held a handsome advantage over a cluster of rivals.
But back-to-back bogeys after poor tee shots at 13 and 14 began to undo his good work, and with the field closing in Storm found himself sharing first place on 12 under with Spaniards Pablo Larrazabal and Gonzalo Fernandez-Castano and Scotland's Scott Jamieson.
Storm signed for a one-under-par 69 on a day when low scoring was widespread, Larrazabal, Richie Ramsay and Henrik Stenson all posting 64s.
"I had two bad swings on 13 and 14," Storm told europeantour.com.
"I had the tournament in the palm of my hand before that, but it should be a good day tomorrow. I've only had two bogeys in 54 holes, which is quite impressive.
"It's difficult leading like I was. I have a lot of things on my mind at the moment with keeping my card, so I'm just looking at getting the best result I can.
"Tomorrow, keeping my card will be in the back of my mind, but I have given myself the chance to win and if I am in there with six holes to go I will go for it."
Larrazabal produced an inspired finish, with five birdies in his final six holes, while both Jamieson and Fernandez-Castano played the back nine impressively in posting rounds of 66.
Of the leading quartet, Storm is arguably the player needing the high finish most of all, given he stands 114th on the Race to Dubai money list, needing to stay in the top 115 to guarantee his place on tour next year.
The Hartlepool man probably needs to win another €100,000 (£80,000) to safeguard his playing rights and a top-three finish in Holland could bring him a six-figure sum. First prize is €300,000 (£240,000).
At the start of the day, Storm led by three from Fernandez-Castano, Jamieson and Sweden's Peter Hanson.
And when he picked up shots at the seventh, 10th and 12th to move to three under for the day and 14 under overall, he was pulling away and looked sure to lead by the end of the day.
Storm dropped his first shot of the week at the 13th, after failing to find the green off the tee.
Rather than a risky chip over a bunker on the direct line to the flag, he played safe and went wide of the potential hazard, leaving himself a long putt for par. It did not drop, meaning it was a bogey for Storm, his lead cut to four.
Then he crunched a wayward drive off the 14th tee and was in trouble that resulted in another dropped shot.
As his pursuers picked up shots over the closing holes, Storm could only manage four straight pars.
Hanson, heading for the Ryder Cup later in the month, birdied the 17th and 18th for a 67 which left him one off the pace on 11-under 199.
Ramsay missed out over the closing holes, but his six-under round lifted him into contention, a further two shots behind. Fresh from claiming the second European Tour victory of his career at the Omega European Masters last weekend, a third could still arrive this weekend for the 29-year-old former US Amateur champion.
He was stationed alongside England's Danny Willett, who had a 66, and Henrik Stenson was on eight-under 202 together with Belgian Nicolas Colsaerts who had a 67 as he continued to build towards his Ryder Cup debut in Medinah.
Germany's former world number one Martin Kaymer, also heading Stateside with Jose Maria Olazabal's Europe team, rolled in a long eagle putt at the last to atone for bogeys at the previous two holes as he finished the day six under for the tournament.
Simon Thornton is the best of the Irish on seven under par. Darren Clarke lies three under, as does Damien McGrane. Peter Lawrie is one under par. Gareth Maybin is four over par.