Italian Marco Pantani may have committed suicide, according to the chief prosecutor in the town where the former cyclist died.
The 34-year-old winner was found dead in a hotel room in Rimini on Saturday after suffering a heart attack.
The cause of death is still unclear, although Franco Battaglino said it may have been drug-related.
"It would not be surprising if Pantani had died because of committing suicide," said Battaglino.
"He was in a big personal crisis."
Battaglino also said his death could have been caused "in relation to the consumption of drugs".
Police carried out further searches on Pantani's Rimini hotel room on Wednesday and also revealed the former Tour de France winner had had five visitors to his room on the day of his death.
Battaglino added: "There are developments we are examining.
"The circumstances that brought Pantani to Rimini are being examined, how it happened and with whom he had contact."
An autopsy into his death revealed the cyclist suffered a heart attack following severe swelling of the heart and brain.
The pathologist's report, which refused to draw any firm conclusions, also said the Italian had lung damage.
"Two elements have emerged, bleeding in the brain and lungs. At this point we can exclude violence," Dr Giuseppe Fortuni said on Monday.
"The investigations will take weeks. We can't rule out any cause of death."
Police said about 10 bottles of tranquilisers of four different brands were discovered in the 34-year-old's room, some of them empty and others just open.
Pantani had been plagued by doping allegations in recent seasons and had suffered from depression.
His death has prompted calls in Italy for athletes suspected of doping offences to be dealt with more sensitively.
Gianni Petrucci, president of the Italian Olympic Committee, which oversees all doping tests in Italy, told RAI state radio: "We all have to believe that we could have done something for Pantani."
Italian sports minister Mario Pescante said Pantani was "a victim of modern sports".
"He was investigated by at least seven state prosecutors. To me, that seems - frankly - too many.
"The penal responsibility of athletes is absurd. Sports sanctions would be enough."