Jannik De Bruyn has four-shot lead in Hamburg at European Open

Rain had made the North Course at Green Eagle Golf Courses play even longer than its colossal 7,458 yards, but De Bruyn made a mockery of the notoriously tough test, birdieing six of his first seven holes and those final four en route to a nine under par total in the DP Tour event.

Englishman Laurie Canter and Wales' Jack Davidson were the nearest challengers, a shot clear of a group containing defending champion Tom McKibbin and another English pair in Dan Bradbury and Garrick Porteous.

De Bruyn made his fast start and added another birdie at the 11th, but back-to-back bogeys on the 12th and 13th allowed Canter to trim the lead to one.

The German had more in the tank, however, and completed his big finish for a score that would have matched the course record had preferred lies not been in place due to the wet conditions.

"I can't explain what happened out there," he said. "But I was just in the moment and the birdies kept coming. I was hitting the ball well in the right areas and my putting was great.

"I was six under through seven and didn't really believe it. I hadn't been playing great coming into the week, so I had no expectation. I was just looking to take it shot by shot and focus on hitting draws. It worked out well for me today."

Canter is back on the DP World Tour after a spell with LIV and even played two events on the Saudi-funded breakaway this year as a reserve.

He carded six birdies and a bogey in his first competitive round with an entirely new set of irons, while Davidson birdied five of his last eight holes.

Northern Ireland's McKibbin recovered from an opening bogey with five birdies as one of the afternoon starters who managed to finish their rounds despite a three-hour fog delay at the start of the day.