It is a baseball term, an idiomatic phrase that we don't even think about. It means they heard one case this week and they get another whack at him next week with a different case. Another one used a lot is "Batting 1000," which would be a perfect record, hitting every ball perfectly every time.

Trump thought he was batting 1000 in the past court cases he's had when he could get away with the criminal behavior (in civil courts to do with housing laws and zoning laws and with bankruptcy and such) - the reason he was called "Teflon Don." Nothing touched him, until now.