Cameron Young will face Sam Burns in the final of the WGC-Dell Technologies Match Play on Sunday evening after the duo pulled off stunning wins over Rory McIlroy and Scottie Scheffler.
McIlroy was two up with three to play before Young turned the tables and bested the Holywood man.
Burns on the other hand needed 21 holes to finally get the better of defending champion and world number one Scheffler.
McIlroy fell behind after making a bogey on the third, but bounced back to birdie the fifth, sixth and ninth for a two-hole lead at the turn.
Both players birdied the 11th before McIlroy hooked his second shot on the par-five 12th from a fairway bunker into the water to see his lead halved.
However, an aggressive tee shot on the short 13th set McIlroy up for a birdie and he remained two up until Young birdied the par-five 16th.
Young also birdied the 18th to force extra holes and the 25-year-old then birdied the first extra hole, the par-five 12th, despite having to pitch out of a fairway bunker with his second shot to leave him 170 yards from the hole.
McIlroy was unable to convert his own birdie putt from nine feet and was no doubt not relishing having to contest the third/fourth-place play-off with Scheffler.
In the first semi-final, Burns made a flying start with a hat-trick of birdies to open up a three-hole lead, but bogeyed the fifth following an errant drive and Scheffler then birdied the sixth and eighth to get back on level terms.
Further birdies on the ninth and 10th, as Burns bogeyed both holes, gave Scheffler a two-hole lead before Burns birdied the 13th and 15th to get back to all square.
Burns almost holed his tee shot on the 17th to edge in front but Scheffler birdied the 18th to keep the match alive and both players birdied the first extra hole.
Scheffler missed from three feet on the 13th to win and Burns took full advantage, holing from 15 feet on the 14th to seal a dramatic victory.
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