That's one thing that bothered me. He has this fancy dagger/sword and he's used it once lol.
Franky and Sanji were literally dominating their CP-9 opponents at the time until they weren't. Same with Zoro and Kaku.
I can give you guys some of the earliest examples of where people 100% would have jumped the gun:
Chapter 184:
Looks entirely as if Usopp knocks out Mr 4
185: Mr 4 is fine because Usopp was lying. Then they proceed to use their tunnels and bombs against them
This LITERALLY looks like they won, except they didn't.
186:
They weren't defeated until the end of this chapter.
And this is the only battle sequence like this.
So I truly do implore people to have an open mind until next chapter. Nothing this chapter implies Jinbe won, there is no narration that says he's the Victor. WsW is not unconscious. There is no indication WsW used his strongest move/moves.
There actually IS an indication that WsW may have no been taking the fight seriously and it got the better of him. WsW asks Jinbe why he's angry all of a sudden. Jinbe also tells him to not fight half assedly.