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.
Philippoussis was playing his first Davis Cup match for two and a half years.
Australia will be among the seeds for next year's World Group, the draw for which will be made on Thursday in Rome.
