Top seed David Nalbandian crashed out of the Buenos Aires Open and his fellow Argentine Gaston Gaudio said he feels like quitting after being jeered off court on Wednesday.
Gaudio, who reached No. 5 in the world rankings in 2005, was trounced 6-1, 6-1 by Ruben Ramirez Hidalgo in his opening match of the tournament, which uses a round-robin system.
"The jeers don't surprise me, they came from the same people who applauded me in 2005," said the sixth seed, who won the tournament two years ago.
"I was a genius then and now I'm an idiot."
"Things don't work without confidence, I'm getting worse and worse and the situation is complicated."
"It makes me want to quit tennis."
Tournament organisers later said that Gaudio is pulling out of Thursday's match against Alessio Di Mauro.
Nalbandian, beaten by Peru's Luis Horna on Tuesday, went down 6-4, 6-4 to compatriot Guillermo Canas.
Canas, who completed a 15-month doping ban last year and arrived in Buenos Aires fresh from winning the Costa do Sauipe tournament in Brazil last week, took advantage of Nalbandian's numerous unforced errors.
Canas will face Horna on Thursday to decide the winner of Group One.
Argentine pair Agustin Calleri and Jose Acasuso were both forced to drop out through injury.
Third seed Calleri, beaten by Albert Montanes on Tuesday, announced he was withdrawing due to back trouble.
Acasuso, seeded eight, pulled out of his match against Diego Hartfield with an elbow injury after losing the first set 6-3.
