Jack Johnson has 23+ recorded fights at the time ,and was fighting in his home town. It is likely Johnson had more undocumented fights and battle Royals prior to being Ko'd by Choynski. This hardly qualifies as being in-experience. I do find it interesting that the better puncher who landed on Johnson either floored him or KO'd him.
Hamburger Journeyman Knocking Out Jack Johnson Joe Choynski knocked out Jack Johnson in 3 rounds. It just shows how overrated Jack Johnson was. No matter how hard Joe Choynski could punch he was 160 or so odd pounds most of his career. No middleweight in history should be able to knock out a real heavyweight. It is funny how most people will still have Johnson high on their all time great heavyweight list because old timers tell them he was great. Harry Greb suffered an early KO so your point becomes invalidated on that.