Steve Hoskins said that when he saw Bonds and his personal trainer, Greg Anderson, coming out of the master bedroom he assumed Anderson had injected the star player with steroids. He testified that he saw the two disappear into that room "once or twice" at each spring training over three consecutive years beginning in 2000.
He also told the jury of eight women and four men that, a year earlier, Bonds had ordered him to research the benefits and side effects of a steroid after the slugger had undergone elbow surgery.
Hoskins was a childhood friend of Bonds' and traveled with him as an assistant until 2003. Hoskins testified that Bonds' significant weight gain concerned him so much that he secretly recorded a conversation with Anderson about steroids so he could convince Bonds' father, Bobby Bonds, that his son was using the drugs.
Bobby Bonds, a former baseball star himself, was suffering from cancer in 2003. Hoskins said he made the recording in front of Barry Bonds' locker in March of that year "to show Bobby actually what really was going on."
"That was the only way to prove it to him," Hoskins said.
Portions of that recording were played for the jury in federal court Wednesday afternoon.
At one point on the recording, Anderson is heard discussing what prosecutors allege are designer steroids he supplied to Bonds. Says Anderson: "But the whole thing is ... everything that I've been doing at this point, it's all undetectable."
Soon after the material was played for the jury, Bonds' attorney Allen Ruby went to work trying to erode Hoskins' credibility. Ruby accused Hoskins of planning to extort Bonds after the player severed business ties with Hoskins during a March 27, 2003, meeting.
During cross examination, Ruby suggested the recording was not made in March -- as Hoskins said -- but was done after the business split, perhaps in April, because Hoskins and Anderson discuss Bonds' slow start to the season.
Hoskins also said he secretly recorded conversations with Bonds' doctor and business lawyer. Hoskins said his recording of Dr. Arthur Ting was made in late 2003 or 2004, in hopes of dissuading Bonds from using steroids.
"I was trying to tell Barry how bad the steroids and drugs actually were," Hoskins said. "I was trying to convey to him from Dr. Ting and others how bad they were."
In morning testimony, Hoskins said he initially served as a kind of valet when Bonds began playing with the San Francisco Giants in 1993, lugging equipment to the ballpark and running personal errands for the slugger.
Under questioning from federal prosecutor Matt Parrella, a jittery Hoskins testified that in 1999 Bonds ordered him to look at the pros and cons of the steroid Winstrol.
"He said 'find out what this steroid does and what the side effects are and is it good or bad,'" Hoskins said.