A 12-foot birdie putt from debuting local favourite Bae Sang-moon helped the International team slash the United States' lead in the Presidents Cup to 5.5-4.5 on Friday.
Daegu-born Bae's putt boosted him, and partner Danny Lee, to a one-up win over Rickie Fowler and Jimmy Walker while Louis Oosthuizen and Branden Grace beat Dustin Johnson and Jordan Spieth 4&3, with Thongchai Jaidee and Charl Schwartzel edging out Bill Haas and Chris Kirk 2&1 in Incheon.
The defending champions' sole four-ball triumph saw JB Holmes and Bubba Watson go two-up on Marc Leishman and Steven Bowditch, with the nervous Americans leading one-up for 14 of 18 holes.
The real intrigue lay with the only halved match of the day. Phil Mickelson and Zach Johnson were handed a one-hole penalty on the seventh when the former breached the 'one-ball condition' by playing a different model of the Callaway ball he had started the match with.
A subsequent statement from the Presidents Cup match committee read: “The committee is not allowed to have Phil go back and play in an attempt to correct the error.
“This is because once any player in the match plays a subsequent stroke, allowing a correction could potentially undermine the strategy already employed by both in the match in completing the hole.”
Keegan Bradley, not a member of this USA team but a former partner of Mickelson in international play, later tweeted his disbelief, writing: “How can you lose a hole twice???! #usgarules #wow”
Mickelson did go on to provide American fans with something to cheer about, however, the left-handed player holing out for an eagle from a fairway bunker on the 12th.