Federal prosecutors are again asking a judge to let them show a jury three drug test results they say show Barry Bonds used steroids.

The judge said last week she was inclined to throw out those results unless someone could directly testify to collecting the slugger's urine samples. The likeliest candidate to be able to do so is Bonds' former trainer, Greg Anderson. A lawyer for Anderson has said his client won't testify at Bonds' upcoming trial.

In a court filing Monday, prosecutors included snippets of Bonds' grand jury testimony saying Anderson collected the samples. It also included testimony from a former BALCO executive saying Anderson dropped off urine samples labeled with Bonds' name.

Bonds is charged with lying to a grand jury about alleged steroid use.