Barry Bonds childhood friend testified Wednesday that the former Giants' slugger asked him to research the effects of steroids in 1999.
Steve Hoskins, who was also Bonds former business partner before a bitter falling out, took the stand Wednesday.
He said Bonds told him to speak with the player's personal surgeon about the positives and negatives of taking steroids.
"He said 'find out what this steroid does and what the side effects are and is it good or bad,'" Hoskins said.
Hoskins said that during that spring training, he saw Bonds and Anderson come out of a bedroom with Anderson holding a syringe, but said he never saw Anderson give an injection.
The conversation was "just that steroids, the shots were making his butt sore," Hoskins testified.
Hoskins said he made cash payments to Bonds' personal trainer, Greg Anderson, on behalf of Bonds. Anderson was sent to prison Tuesday for refusing to testify in the trial.
Because Anderson has refused to testify, Hoskins has become a key witness in prosecutors' bid to prove that Bonds did take steroids and lied to the grand jury.
Because Anderson has refused to testify, Hoskins has become a key witness in prosecutors' bid to prove that Bonds did take steroids and other drugs and therefore lied to the grand jury.
Also Wednesday, the federal investigator who headed up the probe that led to the Bonds' perjury case has finished testifying on day three of the slugger's trial Wednesday.
Jeff Novitzky is now an agent with the Food and Drug Administration, and on Wednesday he discussed which government officials created the transcripts of a recording made by Steve Hoskins, Bonds' former business partner.
Novitzky was described as "unflappable" on the stand when being questioned by Bonds' attorney Allen Ruby.
Hoskins took the witness stand after the agent's testimony and was expected to testify extensively about the recording he made secretly of a conversation about steroids he had with Bonds' former personal trainer, Greg Anderson.
Bonds is accused of lying to a grand jury in 2003 when he said did not knowingly take performance-enhancing drugs.
On Tuesday, Novitzky told the jury how back in 2002 he regularly searched the trash of the Bay Area Laboratory Co-Operative, best known as BALCO, for evidence of drug use back. BALCO was the headquarters of an international steroids ring that was broken up through investigators' efforts.
The Associated Press and Bay City News contributed to this story