A boxer is watching the super featherweight champion fighting and praises his speed:
あの速さにダメージを与えるため〝芯〟を射抜くのは【フル】ラウンドでも難しい…！！ ベルトをとった あの王者の… 武器【スピード】の前では。
Considering the context, I think that in the second sentence he is saying that what allowed the champion to win the belt is his speed. Could 〜の前では have the meaning of "thanks to"? Otherwise, I don't know how to interpret it here. Is it a grammar structure I am unaware of? Has something been omitted? Is the sentence incomplete? Thank you for your help!