Johnson has one major title to his name, but - outside of Koepka - none of the other players within two shots of the lead have claimed one of golf's biggest trophies. The lack of winning experience certainly has the four-time major champ feeling good about his chances on Sunday at TPC Harding Park.
"A lot of the guys on the leaderboard, I don't think have won. I guess DJ's only won one, but I don't know the other guys that are up there," Koepka told CBS Sports' Amanda Balionis after the round. "A lot of experience, I guess, is what I can bring to it. Know that I've been in this position quite a few times over the last couple years."
It's tough to argue with the sixth-ranked golfer in the world, as his results in major championships have been incredible since breaking through with his first victory at the 2017 U.S. Open. In the nine majors since, he's racked up three wins, two second-place finishes, and two other showings inside the top-6.
Johnson has been agonizingly close to several other major wins, finishing second on four separate occasions. The 2010 U.S. Open saw Johnson in the final group, but a disastrous showing resulted in an 82 on Sunday, dropping him from contention. The 2010 PGA Championship was also heartbreaking for Johnson, who took a two-stroke penalty for grounding his club in a bunker on the 72nd hole to miss a playoff. On the final hole of the 2015 U.S. Open, the South Carolina native three-putted from 12 feet, going from potentially winning to missing a playoff with Jordan Spieth.
Sunday in San Francisco will be the 36-year-old's latest attempt to end his final-round major struggles, but he can surely expect a stiff challenge from the confident Koepka.