When have boxers used a completely different boxing style and won ?

[real raw]

Oh yeah, I remember that fought. It was the second one, right?

I remember in an interview. Tyson Fury said "Deontay Wilder is used to coming forward with his devastasting right hand that has slept many of his opponents and no-one backing him up." So they came up with a forward strategy and got the win!

More like he employed the offensive lineman strategy, lol. But it was effective and it worked

[Damn Wicked]

Sugar Shane Mosley completely changed his style and strategy when he fought Margarito. He would blast him quickly from the outside and then immediately close distance and hold Margarito/ tie him up, forcing the ref to have to break up the action. Mosley rinsed and repeated this until Margarito was beaten down. It was an effective strategy to prevent Margarito from getting his offense going. It could also have been seen as "using illegal tactics" but the ref allowed it so in that fight it was perfectly legal.