Well, in basketball I'd call it "setting a pick". In football I'd call it "blocking". In hockey, I'd just call it "normal game play".
Oh, wait... no... they'd have to smash the other robot into the boards to make it "normal game play".
But if B is blocking one side of the field, the opposing alliance sends three robots down... one ties up B, the other two go fill up with discs.
B might slow them down, but certainly won't stop them.
Jason