India's Shubhankar Sharma remains on course to claim a remarkable third win in eight events in the WGC-Mexico Championship after holding onto his lead at Chapultepec Golf Club.
Meanwhile Paul Dunne posted his best round of the weekend on Saturday - but his 72 leaves him seven over par for the tournament, in 58th place.
Sharma was outside the world’s top 450 when he won the Joburg Open in December, but proved that was no fluke with a second European Tour title in the Maybank Championship in Malaysia last month.
Those victories took the 21-year-old to the top of the Race to Dubai and secured a World Golf Championship debut in Mexico City, where an elite 64-man field is competing for a winner’s cheque of £1.2million from a total prize fund of £7.2million.
And after opening rounds of 65 and 66 gave Sharma a two-shot lead at the halfway stage, the world number 75 added a third round of 69 to finish 13 under par, two ahead of Masters champion Sergio Garcia, five-time major winner Phil Mickelson, Tyrrell Hatton and Rafa Cabrera Bello.
Hatton had been suffering from a bout of food poisoning earlier in the week but the world number 16 showed no ill effects as he raced to the turn in 30, chipped in for a birdie on the 12th and almost repeated the trick for an eagle on the 15th.
“I definitely feel better, it was only an issue Wednesday night really and the Imodium has helped a lot,” Hatton told Sky Sports after a flawless 64.
“I got off to a good start, felt comfort with my game and was five under through nine which I was over the moon with.
“I felt like I lost my swing a little on the back nine but overall if you said I was going to shoot seven under at the start of the day I’d have been buzzing so very happy with that.”
Mickelson, 47, who has not tasted victory since the 2013 Open at Muirfield, also did not drop a shot in his 65, while the Spanish pair of Garcia and Cabrera Bello both shot 69.
Defending champion and world number one Dustin Johnson is three shots off the pace on 10 under par alongside Pat Perez, Xander Schauffele and Brian Harman, with world number two Justin Thomas another stroke adrift.
Thomas, who is seeking back-to-back wins after victory in the Honda Classic on Sunday, was 11 shots off the pace at the start of the day but fired eight birdies and an eagle in a course record of 62.
Collated third round Scores in the Mexico Championship: (Gbr & Irl unless stated, par 71):
200 Shubhankar Sharma (Ind) 65 66 69
202 Phil Mickelson (USA) 69 68 65, Sergio Garcia (Spa) 68 65 69, Tyrrell Hatton 70 68 64, Rafael Cabrera-Bello (Spa) 66 67 69
203 Dustin Johnson (USA) 69 66 68, Pat Perez (USA) 68 67 68, Xander Schauffele (USA) 65 68 70, Brian Harman (USA) 68 67 68
204 Justin Thomas (USA) 72 70 62
206 Brendan Steele (USA) 69 66 71, Tony Finau (USA) 68 70 68, Kiradech Aphibarnrat (Tha) 66 69 71, Charley Hoffman (USA) 70 66 70, Marc Leishman (Aus) 69 68 69, Jordan Spieth (USA) 70 67 69
207 Kyle Stanley (USA) 71 65 71, Bubba Watson (USA) 69 66 72, Kevin Kisner (USA) 70 71 66, Jhonattan Vegas (Ven) 70 68 69
208 Adam Bland (Aus) 70 67 71, Ross Fisher 71 68 69, Jon Rahm (Spa) 67 71 70, Adam Hadwin (Can) 70 71 67, Rickie Fowler (USA) 68 70 70
209 Daniel Berger (USA) 69 68 72, Paul Casey 73 68 68, Patton Kizzire (USA) 69 69 71
210 Charl Schwartzel (Rsa) 71 69 70, Alex Noren (Swe) 69 70 71, Tommy Fleetwood 72 71 67
211 Francesco Molinari (Ita) 71 70 70, Joost Luiten (Ned) 72 71 68, Louis Oosthuizen (Rsa) 64 71 76, Chris Paisley 65 75 71, Thomas Pieters (Bel) 69 68 74
212 Jason Dufner (USA) 72 72 68, Jorge Campillo (Spa) 72 71 69, David Lipsky (USA) 70 71 71
213 Russell Henley (USA) 69 69 75, Chez Reavie (USA) 72 73 68
214 Branden Grace (Rsa) 72 69 73, Dylan Frittelli (Rsa) 73 70 71, Patrick Reed (USA) 72 74 68, Matthew Fitzpatrick 71 69 74
215 Yuta Ikeda (Jpn) 73 74 68, Wade Ormsby (Aus) 79 67 69, Kevin Chappell (USA) 73 70 72, Webb Simpson (USA) 72 70 73
216 Peter Uihlein (USA) 74 72 70, Justin Rose 71 72 73, Patrick Cantlay (USA) 70 75 71, Bernd Wiesberger (Aut) 73 71 72
217 Dean Burmester (Rsa) 73 70 74
218 Satoshi Kodaira (Jpn) 72 73 73, Abraham Ancer (Mex) 71 76 71, Gary Woodland (USA) 74 71 73
220 Paul Dunne 73 75 72
221 Matt Kuchar (USA) 74 74 73
222 Brandon Stone (Rsa) 75 76 71
223 Yusaku Miyazato (Jpn) 77 72 74
224 Brett Rumford (Aus) 78 74 72
225 Haotong Li (Chn) 73 79 73, Gavin Green (Mal) 78 73 74
