Injury has forced former Wimbledon champion Richard Krajicek to pull out of next month's Masters event at London's Royal Albert Hall.
The Dutchman has a knee injury and will be replaced by compatriot and defending champion Paul Haarhuis.
Haarhuis, who beat Jim Courier in last year's final, completes the 12-man field at the 5-10 December.
Tim Henman will put his fitness to the test in an exhibition match against Mark Philippoussis on 5 December.
Haarhuis joins John McEnroe, Goran Ivanisevic, Pat Cash, Richard Krajicek, Marcelo Rios, Thomas Muster, Sergi Bruguera, Cedric Pioline, Henri Leconte and Carl-Uwe Steeb at the Royal Albert Hall.
And Britain's Jeremy Bates and Sweden's Anders Jarryd have been confirmed as wildcards for the US$100,000 event.
The doubles field has also been revealed, with McEnroe's former partner Peter Fleming, Mansour Bahrami, Peter McNamara, Mats Wilander, Jacco Eltingh, Paul Haarhuis, Tom Gullikson and Chris Wilkinson set to appear.