World number one Dustin Johnson beat Zach Johnson and Phil Mickelson continued his strong form to reach the WGC-Dell Match Play quarter-finals in Texas on Saturday.

Dustin Johnson used birdies on 13 and 14 to end the match as he defeated double champion Zach Johnson 5&4 in the round of 16 to advance to the last eight, where he will take on Sweden's Alex Noren later on Saturday.

Noren was a 3&1 winner over American Brooks Koepka at Austin Country Club.

Five-times major champion Mickelson advanced with a 4&3 victory over in-form Australian Marc Leishman.

Mickelson, who took three holes in a row at the turn to go 5-up, will next take on fellow American Bill Haas, 1-up winner over compatriot Kevin Na.

England's Ross Fisher also advanced, defeating American Bubba Watson 4&3.

Spain's Jon Rahm beat American Charles Howell 6&4, Denmark's Soren Kjeldsen overcame American William McGirt 5&4 and Japan's Hideto Tanihara edged out England's Paul Casey 2&1.