I think my girlfriend's guy friend likes her?

My girlfriend has this guy friend named Jacob who she is very close to, they are best friends. Well I think he has a crush on her because every time he sees me he keeps telling me why he is better than him and he always start a fight. He started a fight with me 3 times and I defended myself and ended up winning. He is 5"7 145 pounds, I am 6"5 285 pounds (mostly muscle, I am football player and a wrestler). I think he has a crush on her, what do you think? Everything is fine between me and her.