NEWPORT, Wales (PA) -- More than 20 European Tour players have now pulled out of Monday's 36-hole U.S. Open qualifier at Walton Heath.

It is the route used by New Zealander Michael Campbell when he won his first major title three years ago. But since the introduction of the England-based U.S. Open qualifying event that season, it has always suffered from a large number of withdrawals.

Among those who have decided to skip the chance to compete in the second major of the year are Darren Clarke, former British Open champion Paul Lawrie, recent Irish Open and Spanish Open winners Richard Finch and Peter Lawrie and Northern Ireland's Graeme McDowell, who is currently 10th in the Ryder Cup race.

Clarke made his decision two weeks ago, saying: "My schedule is firmly based around Europe and my goal is to make the Ryder Cup team."

He and others believe that a trip out to Torrey Pines in California if they made it through the qualifier was not going to benefit them in the coming weeks.

Just over a week ago, a total of 76 players were listed for the qualifier, but that is now down to 50. And organizers could well be asking golfers in America who just failed at local qualifying level if they fancy filling the gaps as alternates at Walton Heath.

Around nine places at Torrey Pines will be on offer at Walton Heath, so there is now a great chance for the likes of 19-year-old Rory McIlroy and Dubliner Paul McGinley to get there.

For McIlroy, the top amateur at last year's British Open, it would be a first major in America.

Miguel Angel Jimenez, Oliver Wilson, Robert Karlsson and Martin Kaymer no longer need to qualify after earning exemptions at last week's BMW PGA Championship.

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