It will be Johnson v Johnson as world number one Dustin takes on double major champion Zach in a round-of-16 clash at the WGC-Dell Match Play in Texas on Saturday.
And five-times major champion Phil Mickelson will meet in-form Australian Marc Leishman as the World Golf Championships event enters the knockout phase after completing the round-robin phase at Austin Country Club.
Big-hitting Dustin Johnson emerged with a perfect 3-0-0 record, wrapping up the group phase with a 5&3 shellacking of fellow American Jimmy Walker on Friday.
He said he fancied his chances of beating namesake and compatriot Zach, not because of the world rankings but because of his form.
“No matter what ranking I am, I feel I should win,” he told reporters. “I feel like I’ve got a bit of an advantage, just because I’m playing so well.
“Today I made a bunch of birdies, no bogeys and usually in match play you do that, you win. Just because I'm number one I don't get a pass. I've still got to play really well.”
Zach Johnson, meanwhile, said he would relish the challenge of taking on the game’s hottest player.
“I think his time is about done. Physically, he is not looking great,” he said, tongue planted firmly in cheek, before turning more serious.
“Hopefully I’ve got my A game. I need it. I expect nothing less out of Dustin. He does things with the golf ball only a small percentage can do out here.”
Mickelson finished group play in style at 3-0-0 with a 6&5 thumping of fellow American J.B. Holmes.
Leishman was given a scare before winning his group in a three-way playoff with Englishman Lee Westwood and American Pat Perez after they all finished with the same 2-1-0 record in their group.
"(I'm) having a good week or so," Australian Leishman, who won the Arnold Palmer Invitational last Sunday, said.
Asked for his thoughts about facing Mickelson, known for his light-hearted trash talking, the laid-back Leishman sounded unfazed.
"I'll have to work on my trash talking I guess," Leishman said. "I've got to keep hitting it the way I have been and make some putts."
Among other round-of-16 match-ups will be Spaniard Jon Rahm versus American Charles Howell III, Englishman Paul Casey against Japan's Hideto Tanihara and American Bubba Watson against Englishman Ross Fisher.
Rahm won his group by beating countryman Sergio Garcia 6&4.
"I'd rather not play a fellow Spaniard but luckily whoever won today was going to make it through," Rahm said.
Howell topped his group after an eventful three-way playoff with Englishman Tyrrell Hatton and Spain's Rafa Cabrera-Bello.
Hatton was eliminated at the first extra hole after incurring a two-stroke penalty for putting without replacing his ball after he had caused it to move fractionally. Howell finally emerged victorious four holes later.
The round-of-16 on Saturday morning will be followed immediately afterwards by the quarter-finals.
(Reporting by Andrew Both in Cary, North Carolina; Editing by Larry Fine)