|Saudi International - First-round leaderboard|
|-9: D Horsey (Eng); -8: S Gallacher (Sco); -6: B Wiesberger (Aut); -5: B DeChambeau (US), M Kinhult (Swe), H Li (Chn), C Hill (Sco), T Pieters (Bel)|
|Selected others: -4: A Sullivan (Eng), L Canter (Eng); -3: I Poulter (Eng), L Westwood (Eng), D Willett (Eng), T Hatton (Eng), J Morrison (Eng); -2: P Mickelson (US); Level: S Garcia (Spa), S Lowry (Ire)|
England's David Horsey said he was in "shock" after a run of seven birdies in eight holes gave him a one-shot lead over Scotland's Stephen Gallacher after round one of the Saudi International.
The 35-year-old's birdie run came on the back nine as he hit a nine-under 61 at Royal Greens Golf and Country Club.
Gallagher holed seven birdies on the front nine and sits on eight under.
Austria's Bernd Wiesberger is six under in third and American Bryson DeChambeau is joint fourth on five under.
Horsey knew an eagle on the par-five 18th hole would have seen him break 60 but he could only make par. Only one player - England's Oliver Fisher - has ever shot a 59 on the European Tour.
"It's a shock actually," said Stockport's Horsey after a round which included nine birdies in all.
"I've been playing rubbish the last couple weeks.
"I had a conversation with a pal back home last night, talking a few things through and he suggested something that I work on away from the tournament.
"Knowing me, I thought, well, can't get any worse, so I may as well try it and here we are."
Gallagher's mark of 62 is the lowest opening round of his career on what is his 584th European Tour start.
Players have faced criticism for participating in the Saudi International due to criticism from human rights groups who believe sport is being used by the country to bury their human rights record.
But the 138-strong field contains stellar names, with world number one Dustin Johnson, who won the inaugural Saudi International in 2019, currently on three under, alongside the likes of England's Danny Willett and Ian Poulter.
Northern Ireland's Graeme McDowell - the event winner in 2020 - is level par, as is Spain's Sergio Garcia and Ireland's reigning Open champion Shane Lowry.