Chang offers explanation

The infielder was suspended from play on Wednesday after testing positive for a banned substance and sat out his team's opening Olympic win over the Netherlands. He apologised to the baseball federation at his hearing.

"Chang told the hearing he had been married for more than nine years and had been unable to reproduce, so in 2007 he saw a doctor, who diagnosed him with infertility, and he began to accept medication," Taiwan's Olympic Committee delegation said in a statement.

"Chang said the results of this doping matter had severely hurt his personal image and the reputation of the Chinese Taipei (Taiwan) team, and he deeply apologises," the statement said.

The IBAF had asked the player to report back to them with a complete medical history as soon as possible, it added.

Chang fell foul of a World Anti-Doping Agency (WADA) check carried out before the Games.

Baseball is Taiwan's most popular sport and offers one of its few chances at winning an Olympic medal.

But the team has lost three of its four games so far, including a defeat on Friday to poorly ranked China that caused shock among fans in Taipei.

Chang's positive test came as another blow to baseball's chances of being reinstated to the Olympic programme.

Major League Baseball's failure to effectively counter the use of performance-enhancing drugs and its refusal to shut down mid-season to allow baseball's best players to take part in the Olympics are viewed as the two main reasons that led to the IOC voting the sport off the Summer Games roster after Beijing.