Thorbjørn Olesen fired the lowest round in BMW International Open history to set the clubhouse target before the overnight leaders had even teed off on the final day at Golf Club Gut Laerchenhof.
There had been a six-way tie for the lead at five under coming into the day and the Dane was seven shots behind after a 77 on Saturday that saw him make an eight on the par three fourth.
The Italian Open winner went 16 shots better than that on Sunday, with a 61 equalling Shubhankar Sharma's lowest round of the season and his 11 under effort being the lowest round to par in 2018.
The astonishing performance containing nine birdies and an eagle got him to nine under par and gave him a three-shot lead over playing partner Justin Walters and Spaniard Nacho Elvira - who were both in the clubhouse - and fellow Dane Søren Kjeldsen, 2008 champion Martin Kaymer, Australian Scott Hend and England's Chris Paisley.
Olesen birdied the second, made an eagle on the par five third and then birdied the ninth to turn in 32 but he truly came to life on the back nine, making seven birdies to come home in 29.
The 28 year old birdied the tenth and 11th and then got on the greens at the par five 13th and 15th in two to make two further gains and move past the leaders.
He then put his tee-shot to ten feet on the par three 16th, his approach to tap-in range on the next and hit a stunning approach to the last for a four-birdie finish and a potentially winning total with the wind beginning to pick up again.
“I felt like the first few days I played really great, especially the second day,” he said. “I was striking the ball fantastic and gave myself so many chances.
As the round progressed I kept on thinking birdies and trying to make the round better. Finishing with four birdies was pretty nice - Thorbjørn Olesen
“I had a bad day yesterday I had a bad hole at the start and obviously that was very disappointing because I felt like I was playing so good.
“I was just trying today to go out there and build on my game, see if I could shoot a low score and get ready for next week. Obviously as the round progressed I kept on thinking birdies and trying to make the round better. Finishing with four birdies was pretty nice.”
South African Walters got off to a birdie-birdie-birdie start and added further gains on the sixth, ninth, 13th, 15th and 16th to continue his good form after finishing in a tie for third at the Shot Clock Masters.
Kjeldsen birdied the first and third and hit a beautiful tee-shot into the par three fourth to join Walters at six under at the turn, and that group began to swell once the leaders got under way.
Hend and Aaron Rai both took advantage of the third, with Lucas Bjerregaard putting his approach to six feet at the second to make it a five-way tie in second.
Kaymer and Paisley both also made the most of the early par five but Rai double-bogeyed the fourth to drop back.
Elvira then joined Walters in the clubhouse three shots off the lead as he birdied five of his last six holes in a 67.
Bjerregaard - in the final group of the day - dropped a shot on the fourth to fall to five under alongside José-Filipe Lima, Thomas Pieters and Matt Wallace.
