Wano might have only been a stage below his opponent, but one must remember that he had already defeated someone stronger than him even though he was injured. Sure, he may have received help from Calina, Malaka, and Kentucky at that time, but during his last attack, he far surpassed his opponent's power.
That being said, he shouldn't have been in a stalemate with this enemy. He kept holding his strength back, waiting for an opportunity to release his full potential in one go. That moment didn't take too long to appear as Kentucky opened a way through the enemies with brute force. The leader couldn't ignore Kentucky, so he immediately turned around to attack the Minokawa.
Seeing that, Wano sheathed his sword and assumed a combat stance. If one looked at that, it would seem quite a slow movement. However, in reality, it was extremely fast. Fire and Wind Element gathered around his body in the next moment.
*Vup!*