London - England's Matthew Jordan stunned the field with a new course record of 63 in the first round of the British Masters on Thursday.
The 23-year-old carded nine birdies in a bogey-free 18 holes at Hillside.
Jordan, in just his 12th event as a professional golfer, ended the day with a two-shot lead over compatriot Matt Wallace and Sweden's Marcus Kinhult.
"You never quite expect it," said Jordan. "I knew I had been playing quite well and just from the get-go it started perfectly and from then on I just kept it going.
"You start to realise you're doing quite well because more people turn up and you see a couple of cameras.
"I was nervous maybe for a couple of holes, like around 11 and 12, and then I settled back into it."
Tournament host and Ryder Cup star Tommy Fleetwood was five shots off the lead after an opening 68, with defending champion Eddie Pepperell two shots further back following a round of 70.
Leading scores from Thursday's first round of the European Tour British Masters at Hillside, England (par 72, GBR and IRL unless stated):
63 - Matthew Jordan
65 - Marcus Kinhult (SWE), Matt Wallace
66 - Thomas Detry (BEL), Richie Ramsay, Robert Karlsson (SWE), Lee Westwood
67 - Sean Crocker (USA), Jack Singh Brar
68 - Tommy Fleetwood, Ashley Chesters, Matthieu Pavon (FRA), Andrew Johnston, Lasse Jensen (DEN), Ross Fisher, Jordan Smith, Scott Hend (AUS), Martin Kaymer (GER), Robert MacIntyre, Dimitrios Papadatos (AUS), Scott Jamieson, Bernd Wiesberger (AUT), Soren Kjeldsen (DEN), Victor Dubuisson (FRA), Niklas Lemke (SWE), Robert Rock, Maximilian Kieffer (GER), Matthew Southgate, Sam Horsfield, Lorenzo Gagli (ITA)