Former Open Champion Darren Clarke is now in doubt for next week’s Masters after withdrawing from this Valero Texas Open with a hamstring injury.

Clarke was set to join fellow Irish Padraig Harrington, Rory McIlroy and Shane Lowry in the $6.2m event starting Thursday in San Antonio.

A hamstring injury forces Darren Clarke out of Valero Texas Open.

However his management company advised Clarke had injured his leg while playing a social round of golf last weekend in the Bahamas.

Also dropping out of the Texas event is Australia’s Geoff Ogilvy, who had just committed to play late last week.

However the 2006 US Open champion easily missed the cut in last week’s Shell Houston and in the prcoess let slip any chance of heading back to Masters by also failing to break into the top-50 on the World Rankings.

Clarke and Ogilvy head a list of late minute withdrawals including South African George Coetzee, currently ranked 43rd in the world, along with Americans Hank Kuehne, Doug LaBelle, Arron Oberholser; and Chris Kirk.

There spots will be taken by Americans Scott McCarron, Joe Durant, Chris DiMarco and former double US Open winner, Lee Janzen plus Australia’s National Green and India’s Arjun Atwal.

Also earning spots in the field, on sponsor exemptions, were German Marcel Siem, who won last week in Morocco on the European Tour, and former PGA Championship winner Rich Beem.

With Ogilvy’s ranking falling, the Texas Open now includes 10 players inside the top 50 in the world rankings, including four in the top 15 headed by World No. 2 Rory McIlroy.