Boyfriend asked me to fight another girl for him

So my boyfriend has a friend who is a girl he has known her years they went to school together and she is like obsessed with him always texting and ringing him even when she knows we’re together she has only met me once and was horrible to me. Anyway I mentioned to my boyfriend I’m not comfortable with him speaking to her since she obviously likes him more than a friend and the fact she is always trying to turn him against me. He said that he will organise a fight and if I win he won’t speak to her and if she wins he can speak to her I was like wtfff and he said if I loved him enough id win and he wouldn’t have to speak to her anymore. I find it so weird how would you react in this situation