World Number 24 Bo Van Pelt and former World Number 3 Englishman Paul Casey are the latest players to join the field for the Perth International in October from 18-21 October.
11-time European Tour winner Casey joins 2011 Masters champion Charl Schwartzel and World Number 9 American Jason Dufner in the field at Lake Karrinyup Country Club.
Van Pelt has enjoyed an outstanding season including ten Top 10 finishes after winning the CIMB Asia Pacific Classic in 2011.
Casey has tasted success in Australia before, winning the former ANZ Championship at NSW Golf Club in 2003.
The three-time Ryder Cup team member has endured a tough year on Tour after finishing in the top 4 of both of his final Tour events in 2011.
Due to the recent cancellation of the Andalucia Masters in Spain, the field has expanded to 156 players to accommodate an increased number of European Tour players expected to attend hunting for points to qualify for the Tour Championship on the Race to Dubai.