SYDNEY (Reuters) - Australia could be in trouble for failing to field appropriate players in their two dead Davis Cup semi-final singles rubbers against Argentina in Buenos Aires on Sunday.

Australia trailed 3-0 after losing the doubles and Tennis Australia said Lleyton Hewitt, Mark Philippoussis and Wayne Arthurs were all carrying injuries.

Doubles player Paul Hanley lost 6-0 6-3 to Agustin Calleri in the first singles on Sunday and the referee awarded a walkover in the fifth rubber to give Argentina a 5-0 win in the tie.

Peter Luczak, with the Australia team as a hitting partner, then beat Argentine Juan Ignacio Chela 7-6 6-4 in an exhibition match.

Tennis Australia is likely to launch an investigation and the International Tennis Federation could ask for an explanation and potentially hand out a fine.

The tie was always controversial for Australia, with Tennis Australia forced to provide extra security for Hewitt following a history of angry confrontations with Argentine players.