Gallacher waited on the leaders to play their rounds after his course record
Stephen Gallacher posted a new course record 63 at Celtic Manor and said that securing his European Tour card had helped him relax into his golf.
The 35-year-old Scot's eight-under-par round at the Wales Open beat the previous course record by two shots.
He missed much of last season through illness and his participation in the tour was not assured until last month.
"Wentworth was big," he said of his fourth place at the PGA. "It took the pressure off for next year."
Gallacher's record round made him the leader in the clubhouse at that stage - level with Germany's Marcel Siem, who was still on the course at seven-under overall.
The Scot had started the day seven off the lead after rounds of 70 and 73 and realised that he was likely to be among the chasing pack once the leaders had recorded their third rounds later in the day.
I've been knackered, but I've just got a wee bit of belief in myself
"It just sets you up to have a good one tomorrow," he said. "It depends on what the guys do today, but it puts me back in the tournament."
This time last year, Gallacher was fighting the viral infection sarcoidosis and even had a biopsy to test for cancer.
He was given an exemption to play on the tour this year, but until a sixth place at the Madrid Masters and his good performance at the PGA at Wentworth he was in danger of losing his card.
"It means I can enjoy it more and be a bit more relaxed and more aggressive," Gallacher said of his latest low score.
"I was a wee bit more aggressive, went for a few flags. It was conducive weather for it, it was beautiful and warm and not much wind.
"I just got the distance control right and I just rolled the putts in at the right time."
Gallacher's health problems were aided by steroid treatment, but he confesses to feeling "absolutely shattered" this week.
"I've been knackered, but I've just got a wee bit of belief in myself," he said.
"My goal this year was to just try and consolidate and make sure I was playing next year and I did it in one foul swoop.
"It's good, it's is just back to where I want to be. You practise hard to be in the last round in with a shout of winning."
Meanwhile, Colin Montgomerie looked haunted by his off-course problems as the European Ryder Cup captain endured a dismal start to his third round.
Montgomerie's participation at Celtic Manor, the course where Europe will face the United States in the Ryder Cup in October, has been overshadowed by newspaper revelations that he is fighting to save his marriage.
The 46-year-old Scot has admitted he and wife Gaynor are "trying to resolve issues" as a result of reports he had an affair with a former girlfriend.
Only four off the lead after two rounds, Montgomerie followed a three-putt bogey on the long second by going in the water at the next and dropping two more strokes.
Montgomerie was suddenly one over par and seven adrift of Siem and Australian Andrew Dodt at that stage before dropping from 14th to 47th by taking a shocking 42 to the turn and handing in a 76.