Matthew Jordan vowed not to get carried away by the prospect of winning £500,000 after making the most of a late tournament invite to card a stunning course record of 63 in the first round of the British Masters.
Playing just his 12th event as a professional, the Englishman defied wet and chilly conditions at Hillside to fire nine birdies and no bogeys and end the day with a two-shot lead over compatriot Matt Wallace and Sweden's Marcus Kinhult.
The 23-year-old from nearby Hoylake turned professional in September 2018 after a stellar amateur career which saw him reach fifth in the world rankings and enjoy a nine-shot victory in the prestigious Lytham Trophy.
"I've known him for a long time, we all know what he's capable of," said tournament host Tommy Fleetwood, who was five shots off the lead after an opening 68.
"That's a tremendous first round and I think it will be good for him now.
"I've seen some of his scores and he's not played as well as I know he wants to this year, but when you're first turning pro it's different and now the experience being at the top of the leaderboard for a few days will be really, really good."
Jordan's best result to date is a tie for seventh in a Challenge Tour event a fortnight ago in Turkey, where he carded a second-round 62, while his career earnings of £57,000 are dwarfed by the first prize of £500,000 on offer this week.
"You never quite expect it," said Jordan, whose younger sister Becky reached the final of Britain's Got talent in 2017 as a member of dance group Merseygirls.
"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 which was strange.
"It's only 18 holes. I'm just going to do what I need to do now and kind of refocus because I know it's going to be tough tomorrow. I need to get into that mindset to go again tomorrow."
Jordan is currently relying on invites after failing to advance beyond the second stage of the qualifying school, but Fleetwood insisted on leaving the decision over who received them this week to European Tour officials, despite the pair's friendship.
"I knew one of his good friends who played with him in the England squad and I said cheekily could I play with Tommy if I ever get the chance," Jordan explained.
"We played a couple of times at Hoylake and he's a really, really nice guy. I got the invitation on Sunday and I'm very thankful to have the opportunity."
Fleetwood admits it is "surreal" to see his face on the side of a bus used to promote the event in the town where he grew up and learnt the game on the local municipal course.
"My dad has even been behind the wheel," the world number 16 said. "It is a pretty special thing for my parents. They've lived in Southport their whole lives and now their son's face is on the side of the bus.
"My dad would probably have to have a few drinks before he admitted how proud he was, so I might have to get a few down him this week. But I can tell how proud they are. When I saw them on Tuesday morning, they were giddy and hyper."
On a day of low scoring, Lee Westwood birdied six of the first seven holes before having to settle for a 66 matched by Richie Ramsay, Robert Karlsson and Thomas Detry, while defending champion Eddie Pepperell shot two under.