"This Dustin thing, I just don't get," Koepka told reporters at the Alfred Dunhill Links Championship in Scotland, according to Golf Channel. "There was no fight, no argument. He's one of my best friends. I love the kid to death. We talked on the phone Monday and yesterday, so you tell me how we fought."
Koepka and Johnson reportedly needed to be separated during an altercation in the European team room after losing the Ryder Cup in convincing fashion.
"People like to make a story and run with it. It's not the first time there's been a news story that isn't true that's gone out," he added.
The Koepka-Johnson rift is one of two reports circulating regarding turmoil on the American side. Patrick Reed is also under fire for comments he made about both captain Jim Furyk and former playing partner Jordan Spieth.
Koepka insisted there was nothing wrong within the American team room.
"As far as camaraderie, it was fine, it was perfect," the three-time major winner said. "The problem is you guys (the media) try to find a reason why we lost and the simple reason is we just didn't play good enough."
Tony Finau, Koepka's playing partner for two sessions during the Ryder Cup, also chimed in on the matter.
"Nothing really to talk about," Finau told Golf Channel at the Alfred Dunhill Links Championship. "I think there is always going to be speculation in the media when a team doesn't win."
"As far as the mood in our U.S. team, it was incredible," Finau added. "We had a great time and all 12 guys, wives, captains, really enjoyed ourselves throughout the week."
After denying the reports, Koepka continued to send condolences to the woman who lost vision in her eye as a result of his errant drive.
"Yesterday was one of the worst days of my life," he said. "I wasn't told what happened until I got here. Nobody feels worse about this than me and it's messed me up inside. I'm heartbroken. Its one shot I definitely regret and hopefully I can speak to her."