Top-seeded Martin Kaymer was eliminated from the World Match Play Championship by the lowest-ranked player in the field on Friday, losing by 1 hole to Richard Finch.
The No. 9-ranked German needed to make a 3-foot putt to halve the match and force a playoff against the No. 218-ranked Finch, but it horseshoed out.
Kaymer, who won the 2010 U.S. PGA Championship, started the year at No. 4 but hasn't won an event this year. He joins Darren Clarke and Charl Schwartzel as major winners who failed to make the weekend.
Defending champion Ian Poulter looked strong after overwhelming Tom Lewis 4 and 3 and extending his unbeaten match-play record on European soil to 14 contests.
Finch made par on the par-5 last and Kaymer should have matched it, but turned away in disbelief after his effort wrapped around the edge of the cup.
Finch's reward is a match against McDowell, who beat Jbe Kruger 4 and 3 and is attempting to recreate his match-play heroics from the 2010 Ryder Cup at Celtic Manor, where he holed the winning putt.
"It was a bit of a dead rubber — the real fun starts tomorrow against Richard," McDowell said.
American Brandt Snedeker was reunited with his own clubs Friday for his head-to-head with Branden Grace. He won his first match with borrowed clubs, a putter from the pro shop and a player's backup driver after his clubs were lost because of an emergency landing Monday during his flight to Spain after a passenger had a heart attack.
It didn't help Snedeker, who lost 4 and 3, but he emerged from a three-way playoff with Grace and Thomas Bjorn to set up a last-16 match with Camilo Villegas.
Bjorn beat Grace on the next playoff hole and will take on Paul Lawrie next.