SAN FRANCISCO – Twenty federal agents raided the home of the mother-in-law of Barry Bonds’ personal trainer yesterday.

Madeleine Gestas and her daughter Nicole Anderson, the trainer’s wife, are the target of a tax investigation that the lawyer for Greg Anderson said is aimed at pressuring the trainer to testify at Bonds’ upcoming trial.

Bonds, baseball’s career home run leader and a seven-time MVP, has pleaded not guilty to charges he lied to a federal grand jury in 2003 when he denied knowingly using performance-enhancing drugs.

“Even the mafia spares the women and children,” said Anderson’s lawyer, Mark Geragos.

Lead prosecutor Matthew Parrella didn’t immediately return a telephone call yesterday.