Among them were those of UFC color commentator Joe Rogan, who says that as ambitious as the current 205-pound champion is, taking on a man who hasn't lost in a decade (Wladimir) and has the reputation as being one of the most powerful punchers the "sweet science" has ever seen, simply isn't a good idea.
And when asked by TMZ if "Bones" would have a remote chance against the current WBA, IBO, WBO, IBF and The Ring Heavyweight Champion, Rogan was as blunt as he could be.
"No, no, no. I think anybody who thinks they can box with one of the very best boxers the heavyweight division has ever seen, without being just a professional boxer for a long period of time, is kind of kidding themselves, or is just the type of person who is a real achiever who likes to set very, very high goals for himself and like maybe have a milestone that he likes to put up there as a possible thing he can have his ambitions set on. But, I don't think it's a good idea. Wladimir Klitschko hasn't lost in a decade and he's been fighting all of the best heavyweight boxers in the world."
Furthermore, following his five-round war against Alexander Gustafsson at UFC 165 last Saturday night (Sept. 21, 2013), a boxing match against a Klitschko is probably not on Jon's mind at the moment, according to Rogan.
Indeed, the damage he took (see it here) in his instant classic in Toronto against "The Mauler" -- which was primarily a stand-up battle -- will probably force Jones to reconsider his goal of stepping into the squared circle against the towering Ukrainian.
Perhaps a move up to the UFC's 265-pound division to take on the competition there would be a good move for Jones before transitioning over to a championship boxing fight, just to see if he can handle the powerful punches the best big men in his sport can dish out.
Still, he likely wouldn't find someone there who can mirror the stand-up skills of a Klitschko.