Who was Vitaly scared more of?

As we all know, Vitaly Klitschko was one of the weakest title-holders in history. The only champion he ever defeated was CRUISERWEIGHT champ Orlin Norris. Now, obviously, there was some very careful match-making on Vitaly's part to build-up his bogus KO record, while having no meaningful victories. This brings an interesting question......Who was Vitaly scared more of, during his career?
Obviously, the first name that comes to mind is Chris Byrd. Byrd took Vitaly's heart (if you want to call it that) during their first fight, and, subsequentely, Vitaly flat out refused to entertain even a mention of the word "rematch"
Then, of course, there's Haseem Rahman. 4 times was the fight scheduled and 4 times Vitaly refused to step in the ring with The Rock. Of course, a true champion , such as, for example, John Ruiz, would overcome Rahman in the very first try. Vitaly, IMHO, realized, that he was not even on Ruiz' level, and that was the reason for his refusal to fight Haseem.
Next up, Oleg Maskaev. As we all know, Oleg made Vitaly quit in the 2-nd round of their fight. When Oleg took WBC belt (by KOing Rahman for the 2nd time, a guy Vitaly absolutely dreaded), Vitaly immediately declared his intention to fight Oleg, only to withdraw from that fight, as soon as he was reminded that Oleg was the same guy who already made Vitaly his bitch 14 years ago.
Next up, was John Ruiz, the most distinguished champion after Lennox TKOed Vitaly and left the sport. Ruiz has victories over Rahman, Holyfield, Kirk Johnson, Oquendo, Golota, while Vitaly has victories over.......I guess, Sanders and Kirk Johnson? Rahman alone on Ruiz' resume is worth five Sanderses.
As we can see, there's no shortage on the list of fighters who Vitaly avoided at all costs (even at the cost of faking a retirement....wink, wink Haseem).
In the board's opinion, who was Vitaly most scared of?

 

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