Shane Lowry will go into the final round at the Vivint Houston Open five shots off the lead.
Sam Burns remains out in front as he goes in search of his maiden victory on the PGA Tour. But the Irishman remains in the mix after a 68 left him four under par. After a fine front nine - with three birdies - he dropped his only shot with a bogey at the 12th.
Burns gradually warmed to his task on Saturday after a sluggish start to his third round at Memorial Park.
The overnight leader failed to get up and down from a greenside bunker on the par-three second and then sprayed his second shot on the next hole across the green before missing a 14ft par putt for another bogey.
He birdied the fourth and eagled the eighth with a fantastic chip from off the green, then ended an entertaining front nine with another bogey after once again finding the sand from the tee.
Another errant drive on the 11th dropped him back but he collected three birdies in four holes from the 13th as he recorded a 68 which moved Burns to nine under overall and a one-shot lead over Jason Day and Carlos Ortiz.
Day would have been level-pegging with Burns heading into the last 18 holes but the Australian three-putted on the 18th in his 67 to sit in a tie for second with Mexico’s Ortiz, who also carded a three-under round on Saturday.
World number one Dustin Johnson hovers menacingly on six under after a blemish-free 66.
Padraig Harrington finished his day tied for 28th at even par following a 71. Graeme McDowell is one over par after shooting a 69.
Collated third round scores and totals in the Houston Open (USA unless stated, par 70):
201 Sam Burns 68 65 68
202 Jason Day (Aus) 67 68 67, Carlos Ortiz (Mex) 67 68 67
203 Sepp Straka (Aut) 68 69 66
204 Dustin Johnson 72 66 66
205 Dawie Van Der Walt (Rsa) 70 66 69, Aaron Wise 70 66 69
206 Tony Finau 69 69 68, Michael Thompson 67 72 67, Hideki Matsuyama (Jpn) 70 70 66, Shane Lowry (Irl) 69 69 68, Patton Kizzire 69 67 70
207 Brooks Koepka 72 70 65, JT Poston 70 67 70, Viktor Hovland (Nor) 70 69 68, Adam Long 68 70 69, Russell Knox (Sco) 69 71 67
208 Talor Gooch 68 69 71, Tyrrell Hatton (Eng) 71 70 67, Will Gordon 76 67 65, Fabian Gomez (Arg) 70 69 69
209 Francesco Molinari (Ita) 70 68 71, Maverick McNealy 71 71 67, Scott Brown 69 68 72, Erik Van Rooyen (Rsa) 71 69 69, Corey Conners (Can) 69 67 73, Cameron Tringale 70 70 69
210 Denny McCarthy 69 72 69, Harold Varner III 67 71 72, Russell Henley 69 72 69, Mackenzie Hughes (Can) 70 72 68, Nate Lashley 73 68 69, Padraig Harrington (Irl) 71 68 71
211 Brian Stuard 73 69 69, Satoshi Kodaira (Jpn) 70 69 72, Kramer Hickok 75 68 68, Charley Hoffman 71 69 71, Graeme McDowell (NIrl) 69 73 69, Adam Scott (Aus) 68 69 74, Austin Cook 71 72 68, Scott Piercy 68 74 69, Max Homa 74 68 69, John Huh 73 69 69, Jhonattan Vegas (Ven) 73 70 68, Troy Merritt 74 68 69
212 Justin Harding (Rsa) 72 68 72, Zach Johnson 73 70 69, Mark Hubbard 69 71 72, Brian Harman 71 69 72, Brandt Snedeker 65 71 76, Jamie Lovemark 73 69 70
213 Greg Chalmers (Aus) 68 73 72, Kevin Chappell 70 71 72
214 Kristoffer Ventura (Nor) 69 69 76, Doc Redman 71 70 73, Scottie Scheffler 67 75 72, Cheng-Tsung Pan (Tai) 72 69 73, Lanto Griffin 72 71 71, Brice Garnett 74 68 72
215 Chris Kirk 73 68 74, Sean O'Hair 71 69 75, James Hahn 71 71 73, Isaiah Salinda 71 69 75
216 Scott Harrington 70 72 74, Erik Barnes 71 72 73, Sungjae Im (Kor) 74 69 73
218 Matt Jones (Aus) 69 72 77
220 Cameron Davis (Aus) 67 76 77
