Which one do you mean ?
If you are talking about Imu/Gorosei it's just that i dont like to over hype a character because of a badass intro or because they defeated Sabo easily.
If you are talking about Kizaru's around top10 ranking then its pretty obvious that there are many characters that are capable to beat him even tho they are more or less on the same level.
Roger,Primebeard and probably Xebec(we have almost zero info about him) and then we can add in there many characters without specific order such as Sakazuki,Shanks,Mihawk,Kaido, Prime Garp etc etc