u have not clue if zoro heard about those fights??? The fact that Mihawk awaits someone stronger than shanks oda could by all means show zoro being ready or near ready for that fight with a simple sky split from the two… additionally we have absolutely no clue what went on during Mihawk training of zoro or what/who they talked about lol Mihawk could have simply told zoro my rival is the yonko shanks you need to surpass him as a swordsman before you come to me 
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