Day was 3up after 8 holes against veteran Jim Furyk and well on the way to victory at Austin Country Club but that’s when Furyk caught fire.
The 2003 US Open champion reeled off three straight birdies to square the match through 11 holes and eventually hit the lead for the first time with a birdie at the par-4 15th.
The match was guaranteed to go the distance once Day squared it again with a birdie of his own at the par-5 16th but he was no match for Furyk who won the par-3 17th with a par and closed out the Queenslander with a birdie at the par-4 18th.
Day – who won the 2016 WGC-Match Play in Austin – still has a slim chance of progressing past the round robin phase and into the round of 16 but will likely need to win his remaining two round robin matches against Henrik Stenson and Phil Mickelson.
From 3 DOWN to 2 UP @DellMatchPlay.March 27, 2019
Cameron Smith also suffered an agonising defeat on day one, 2up on American Charles Howell III before losing the match 2&1.
Smith lost four holes in a row from the 13th and halved the 17th for the loss.
Marc Leishman fared much better in his opening match, beating Thailand’s Kiradech Aphibarnrat 2up.
The Victorian was never behind in the match though gave up the lead three times in the first 11 holes.
Wins at the 12th and 16th put Leishman 2up with two holes to play and he could afford to lose the 17th before a closing birdie for the win.
Leishman will play Scot Russell Knox tomorrow while Smith will face off against reigning Australian Open champion Abraham Ancer.
The 64-man field is divided into 16 groups of 4 players and only 1 player from each group advances to the round of 16 on Saturday US time.
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