Hamburg - American Bryson DeChambeau fired a six-under-par 66 to take a one-shot lead after the opening round of the European Open in Hamburg on Thursday.
The US Ryder Cup hopeful, playing a regular European Tour event for only the second time since 2016, started on the back nine and made seven birdies, including one on his final hole.
"It's great to start out with six under par. I think it's one of my lowest rounds on the European Tour so I'm very pleased," DeChambeau told europeantour.com.
"I haven't been hitting it my best so I'm still working on my game and it's starting to turn into some form.
"I'm missing in the right places and making some putts which is great. If you do that out here you're going to be up there."
The 24-year-old has shown some strong form this year, winning the Memorial Tournament last month, and sits just one spot outside the eight automatic qualification places for the United States Ryder Cup team for the showdown in Paris in September.
Three Frenchmen - Joel Stalter, Romain Wattel and Mike Lorenzo-Vera - are tied for second with home hope Benedict Staben on five-under in Germany.
World No 15 Paul Casey, who has returned to the European Tour in a bid to qualify for the Ryder Cup for the first time since 2008, had an eagle on the par-five 18th hole in a three-under 69.
Masters champion Patrick Reed struggled before closing with back-to-back birdies in an opening 70, level with 2011 Masters winner Charl Schwartzel.
Leading first-round scores from the European Tour's European Open in Hamburg, Germany on Thursday (par 72/GBR & IRL unless stated/* denotes amateur):
66 - Bryson DeChambeau (USA)
67 - Joel Stalter (FRA), Romain Wattel (FRA), Benedict Staben (GER), Mike Lorenzo-Vera (FRA)
68 - Andrew Dodt (AUS), Steven Brown, Scott Hend (AUS), Lasse Jensen (DEN), Matthias Schwab (AUT), Viktor Hovland (NOR*), Oliver Fisher, Bradley Dredge (WAL), Allen John (GER*), Connor Syme
69 - David Lipsky (USA), Hideto Tanihara (JPN), Paul Casey, Nicolai Hojgaard (NOR*), Maximilian Kieffer (GER), David Drysdale, Choi Jin-ho (KOR), David Horsey, Philipp Mejow (GER), Alexander Levy (FRA), Soren Kjeldsen (DEN)
70 - Patrick Reed (USA), Charl Schwartzel (RSA)