PGA tour leader Jason Dufner and 18th-ranked Zach Johnson separated themselves from the field on Saturday at the Crowne Plaza Invitational in Fort Worth.

Dufner entered the clubhouse at 15 under, after finishing with a 4 under 66 on the day. Hot on his heels was Zach Johnson at 14 under, after a solid 5 under 65 on his scorecard. The pair are 7 and 8 shots ahead of the rest of the field going into Sunday's final round at the Colonial Country Club.

Tom Gillis is in 3rd at 7 under and Bo Van Pelt has sole possession of 4th place at 6 under for the tournament, with two golfers tied for 5th and 7 men tied for 7th place at the end of day three.

A warm and muggy forecast awaits on Sunday with partly cloudy skies and a forecast high of 92 degrees.