Paul Dunne will take a one-shot lead into the second round of the Turkish Airlines Open but he has an elite chasing pack breathing down his neck at Regnum Carya Golf & Spa Resort.
The Irishman fired a brilliant bogey-free 64 to get to seven under on day one of the season's sixth Rolex Series event, with defending champion Justin Rose, 2016 winner Thorbjørn Olesen and three-time Major Champion Padraig Harrington just a shot back.
There was then a group of seven players in the group two shots off the lead including former World Number Ones Martin Kaymer and Lee Westwood.
Thai Kiradech Aphibarnrat, Belgian Thomas Detry, England's Sam Horsfield and Chinese pair Li Haotong and Wu Ashun were also at five under in a top ten with 74 European Tour wins between them.
Dunne is searching for his second victory in Antalya, while a triumph for Olesen or Rose would see them join Alex Noren and Jon Rahm as multiple Rolex Series winners.
A win would also take Rose back to the top of the Official World Golf Ranking after achieving 23 top tens in his last 30 worldwide starts.
Harrington has 15 European Tour wins to his name, including those three Majors, and the 47 year old arrived in Turkey off the back off three top tens in his last six starts.
Dunne has not registered a top ten since the Volvo China Open in April and was delighted to be back at the top of the leaderboard.
“I just haven't been hitting the ball very well,” he said. “My putting is okay, I kind of drove it the same but lost my iron play a little bit. I just scrambled for par for three months, really.
“It's nice to see a bit of form, post a good score and get a bogey-free round on the card. The holes I needed to hit a good shot on, I stepped up and hit a really straight one.”
Harrington began his round with three birdies and Dunne had gains on the 11th, 13th and 15th to join the early group at the top.
A four-foot putt on the fifth handed Harrington the lead but Dunne joined him with a birdie on the 18th before trouble off the tee on the seventh led to a first bogey of the day for Harrington.
A second consecutive gain on the first then handed Dunne a two-shot advantage but a stunning approach to the ninth put Harrington within one.
He holed a six-footer at the par-five 12th to get into a share and when he followed it with another gain on the next, he was one clear of Dunne.
The 2017 British Masters champion would not be denied, however, and he holed an eight-footer on the seventh before rolling in a long right-to-lefter on the tenth to set the target.
Rose made a spectacular start, holing out from the fairway on the fourth for an eagle before an 18-foot putt brought a birdie on the next. The Englishman holed an eight-footer on the eighth to turn in 30 before getting on the par-five 15th in two and holing from eight feet again on the last.
Dane Olesen battled for par on his first three holes but a birdie on the fourth settled him and he made further gains on the seventh and ninth to turn in 31. An excellent tee-shot on the par three 14th was sandwiched by birdies on the par-five 12th and 15th to move him within one of the lead.
Westwood and Detry were bogey-free for their rounds, while Li chipped in twice - including for an eagle at the 12th - in his 66.
Horsfield also eagled the 12th in his round, with Aphibarnrat making two bogeys, while Wu and Kaymer each dropped a single shot.
Malaysian Gavin Green, Frenchman Alexander Levy, Australian Jason Scrivener, American Julian Suri, South African Erik van Rooyen and English trio Chris Paisley, Matt Wallace and Danny Willett were all at four under.