Organisers are still trying to fill the last three places in the 12-man field for the Cisco World Match Play championship at Wentworth on October 11-14.
Five members of the European side who would have been playing in the Ryder Cup next week - Lee Westwood, Colin Montgomerie, Darren Clarke, Padraig Harrington and Thomas Bjorn - are taking part.
But so far there is nobody from the American side which has taken the decision not to travel to The Belfry in the wake of last week’s terrorist attacks.
The other players committed to the £1m event so far are US Open champion Retief Goosen, Fiji’s Vijay Singh, Australian Robert Allenby and Canadian Mike Weir.
Westwood defends the title he took by beating Montgomerie at the second extra hole, having previously knocked out Sergio Garcia and Ernie Els in the two previous rounds.
It was one of seven victories by Westwood last season but it remains his last win.
First prize is again £250,000 and Mark McCormack, whose International Management Group run the event, said: ‘‘The postponement of the Ryder Cup and the understandable uncertainty over whether some players are willing to travel means he cannot confirm the names of all 12 players at this stage.’’