Matt Kuchar turned the screw in the third round of the Mayakoba Golf Classic as he extended his lead to four shots.
The 40-year-old American had carded back-to-back 64s to lead by two at the halfway stage in Mexico and he produced another impressive round for a six-under 65 to move to 20 under – a new tournament record after 54 holes – at El Camaleon Golf Club.
South Korea’s Whee Kim heads the chasing pack on 16 under with American Richy Werenski and Danny Lee of New Zealand a shot further back.
Kuchar, who won the last of his seven PGA Tour titles at the 2014 RBC Heritage, turned in 32 after maintaining his grip on the tournament with birdies at the third, fifth, seventh and eighth.
Further gains followed at the 12th and 13th before he recorded his only bogey of the day at the par-four 14th where he hit a wild drive into the mangroves, although he quickly made amends with a birdie at the par-three 15th.
He could then only make pars on the closing three holes as he failed to make it a hat-trick of 64s but he still looks firmly on course to complete a wire-to-wire success.
Kim enjoyed a superb run on the front nine with birdies at the fifth, seventh, eighth and ninth, but he could only add one further birdie – at the 15th – on the way home as he posted a five-under 66.
Werenski, who had four birdies on a flawless back nine, and Lee both signed for 67s to share third spot on 15 under.
Aaron Wise hit the round of the day – an eight-under 63 – to move into a share of fifth place on 14 under with JJ Spaun (65) and Cameron Champ (69).
Rookie Champ had stormed into contention with a 62 on Friday and was only four off the lead when he holed a long-range putt for a birdie at the 17th.
However, he then made a mess of the last with a poor chip from the back of the green and three putts for a double-bogey which left him with a 69.
USA Ryder Cup captain Jim Furyk continued his encouraging week with a five-under 66 which put him in a share of eighth place on 13 under.
India’s Anirban Lahiri was tied for the lead with Kuchar early on the front nine, where he had five birdies, but two bogeys and a double-bogey at the 14th on the back nine saw him slip back to 13 under alongside Furyk.
Tony Finau is on 12 under after a 67, with his Ryder Cup team-mate Rickie Fowler on 10 under following a 69.
