Tyrrell Hatton admitted he found one-on-one golf stressful as he moved to within half a point of advancing to the last-16 at the 2022 WGC - Dell Technologies Match Play.
The Englishman is a two-time Ryder Cup player and has twice advanced from the group stage at Austin Country Club, so his match play credentials are not in doubt.
But after a 1 Up win over Si Woo Kim where he had to win the last despite not dropping a shot all day, Hatton revealed he felt the format was a "mental battle".
"It's definitely more stressful for me," he said. "Obviously you're playing against one man and it's definitely a mental battle.
"We all get good breaks, we all get bad breaks, but I guess in match play you kind of want to see less of that when you're playing against someone else. So yeah, it's more stressful in that sense."
Hatton birdied the first and fifth to go 2 Up but Kim made a gain of his own to trim the gap at the ninth.
A birdie at the 12th tied things up but Hatton won the 15th with a par before Kim birdied the 17th.
The South Korean then produced a poor tee-shot on the last that allowed Hatton to take the win with a par.
In the other match in Group 13, Daniel Berger kept his hopes alive with a 2 & 1 win over the now-eliminated Christiaan Bezuidenhout.
Seamus Power is in control of Group Four after a 5 & 4 victory over Patrick Cantlay.
The Irishman won the first, fifth and ninth with pars as he turned 2 Up and won the tenth and 14th in the same fashion, with Cantlay conceding the 13th after finding the water.
"I thought it played a little trickier today," said Power. "It was starting to firm up and get a little faster out there. I didn't make too many mistakes and obviously I caught Patrick on a day when he didn't play his best, so I was able to take advantage and it was great to get a point."
Cantlay is now eliminated alongside Keith Mitchell, who lost 5 & 3 to Sungjae Im.