Shane Lowry shot a stunning 63 to take a four-shot lead into the final round of The Open Championship.
The Irishman started Saturday as co-leader with J.B. Holmes but ended the day six shots clear of the American, with Tommy Fleetwood now his nearest rival.
Having shot back-to-back 67s, Lowry's blemish-free third-round tally represented the best score of the week so far at Royal Portrush as he moved to 16 under overall.
But he faces a stiff challenge on Sunday, not only from fellow maiden major hopeful Fleetwood, but also the weather, with tee times having been moved forward amid a forecast of potential storms.
And it is not only the conditions that will test Lowry, who led by four going into the last round of the 2016 U.S. Open at Oakmont before collapsing and finishing three back of Dustin Johnson, as four-time major winner Brooks Koepka is one shot behind Holmes on nine under, along with Justin Rose.
American Holmes had got to 11 under by the 12th but his round stalled before a birdie at the last, while Lee Westwood endured a back-nine decline to fall eight shots back.
The likes of Jon Rahm, Jordan Spieth, Tony Finau and Danny Willett on seven under almost certainly have too much work to do.
On a warm and relatively calm day in Northern Ireland, it was Lowry who capitalised most to turn in a scorecard that boasted eight birdies.
Met with raucous applause onto every tee, he left most greens with a similar din ringing in his ears as his putter ran hot in a superb all-round display.
Lowry birdied 15, 16 and 17 and very nearly nailed a 25-foot putt for another gain at 18, which would have equalled the best score in Open history, but settled for a par to seal the greatest round of his life.
He will hope Sunday brings an even greater reward.