Injury-hit Gustavo Kuerten suffered another setback when he lost 6-3 6-7 (5-7) 7-6 (7-4) to local player Agustin Calleri in the first round of the Argentine Open today.
Calleri needed two hours and 19 minutes to overcome a battling Kuerten, who entered the tournament as top seed despite a poor run of form due to a persistent hip injury.
The Brazilian had previously played only one match this season, a five-set defeat to Julien Boutter in the first round of the Australian Open.
In another first round upset, second seed Guillermo Canas lost 6-2 6-3 to Spain's David Sanchez.