Paul Casey trailed Geoff Ogilvy over the opening holes as the World Golf Championships - Accenture Match Play final got under way.
Casey got off to a shaky start at the Ritz-Carlton Golf Club near Tucson when, after a great approach shot at the par four first hole, he missed his birdie putt from four and a half feet.
Ogilvy holed out from six feet and took a one up lead in the 36 hole match.
The pre-match ceremonials were conducted in a relaxed atmosphere as England's Casey and Australian Ogilvy are friends, and both members at the Whisper Rock Golf Club in Scottsdale, Arizona.
They even played a practice round together at the new Jack Nicklaus designed Ritz-Carlton course a little over two weeks ago and their preparations paid dividends as Casey advanced to the final with a semi-final win over fellow Englishman Ross Fisher.
Ogilvy, having knocked out two in form players in Camilo Villegas of Colombia and Northern Ireland's Rory McIlroy in previous rounds, defeated last year's runner-up Stewart Cink in his semi-final.
Ogilvy and Casey matched each other over the next four holes to leave the Australian one up after five.
Cink and Fisher contest an 18 hole match for third place later, before the finalists begin their second round in search of the US$ 1.4 million first prize.
