England's Ian Poulter is the first major upset at the $US9 million World Match Play Championship, losing to American Rickie Fowler 2 and 1.
Poulter, who won the Match Play crown in 2010, reached the semi-finals last year before losing to Hunter Mahan.
But the world number 15 crashed out in the first round this year at the hands of Fowler, who birdied to win the fourth and took the par-3 sixth and par-four seventh with pars to lead early on 3-up.
Fowler, a 14th seed in the quarter of the draw topped by Northern Ireland's Rory McIlroy, advanced to a second-round match against the hottest player on the US PGA Tour, fellow American Jimmy Walker.
Walker, seeded sixth, eliminated South African 11th seed Branden Grace 5 and 4.
Walker has won three PGA titles already this season, capturing the 2013-2014 opener at the Frys.com Open, adding the Sony Open in Hawaii last month and taking the Pebble Beach National Pro-Am just 10 days ago.
