Justin Rose knows no lead is safe on the PGA Tour.
The 37-year-old Englishman shot 4-under-par 66 in 100-degree temperatures in the third round and is four strokes ahead of Emiliano Grillo of Argentina and Brooks Koepka heading to the final round of the Fort Worth Invitational at Colonial Country Club in Fort Worth, Texas.
“I am really happy with the way I am playing and I enjoyed the day out there,” said the fifth-ranked Rose, who birdied the first three holes and made his only bogey at No. 16. “It was nice to get going early and build the lead. I wanted to get as far ahead as I could. I struggled a little coming home in the heat.
“I have to keep going and not only make pars because I know the chasing pack is coming and those guys can go low. I have to keep playing one shot at a time and just continue what I’ve been doing.”
Rose, the 2013 U.S. Open champion and 2016 Olympic gold medalist who has eight PGA Tour victories, recorded a 54-hole score of 14-under 196.
Koepka, who won the U.S. Open last year, overcame a double-bogey 7 on the 11th hole to shoot 67, while Grillo, whose only PGA Tour victory came in the 2015 Frys.com Open, finished at 69.
Corey Conners of Canada birdied five of the last six holes in a 63 and is six shots behind in a tie for fourth with fourth-ranked Jon Rahm of Spain and Louis Oosthuizen of South Africa, who both had a 64s, J.T. Poston, who totaled 65, and Ryan Armour, who wound up at 66.
Ted Potter shot 63 and is one more down in a tie for ninth with Brian Harman (64), Kevin Tway (68), Derek Fathauer (66) and Ben Crane (66).
Sixth-ranked Rickie Fowler of Murrieta is tied for 21st after a 69, third-ranked Jordan Spieth, who won at Fort Worth two years ago, shot 70 and is tied for 38th, and defending champion Kevin Kisner is tied for 67th following a 71.