Casey and Karlsson were team-mates on the winning Ryder Cup team two years ago, so they both knew what they were in for.

The Englishman made a sizzling start with birdie at the first four holes before Karlsson responded with birdies and two holes later it was all square.

“I knew it was going to be incredibly difficult, and he proved me right,” said Casey. “It did go through my mind that I could shoot 64 and lose. It was very close but I’m very happy to get through. I don’t like playing friends in match play but I’m very, very happy with the way I played.”

This is the second year the World Golf Championships event has been held in the foothills overlooking Tucson, and Casey for one is glad it moved from its old site at the invariably soggy La Costa, near San Diego.

Dove Mountain, at 3000 feet elevation, is high enough to make players think twice before pulling a club for their approach shots.

“I know desert golf very well, know how to play it,” he said. “I know how far the ball goes, know how the ball reacts coming out of the rough. Maybe that’s a small advantage, but it’s still an advantage.

“Pitching wedges that were going 135 yards last week in LA are going 150 yards here. I have no equation for it. I don’t explain it to my caddie. He just gives me the yardage and I pull a club and just kind of know.”

Meanwhile, Ian Poulter was not quite as impressive as Casey, but still got the job done with a two and one victory over Dane Soren Hansen in another all-European contest.

The pivotal hole was the par-three 14th, where Poulter sank a monster birdie from outside 60 feet to take a crucial one-up lead.

“It was a tight match the whole way,” said Poulter.

Colin Montgomerie, Lee Westwood, Bradley Dredge and Luke Donald also won to advance to the last 32 along with Open champion Padraig Harrington, Spaniard Sergio Garcia and Swedes Henrik Stenson and Niclas Fasth.