Still remember the first guy I lost to in the career mode in the first Knockout Kings: Clean Your Clock Kelly by UD
Knockout Kings 2001 for PS1 (PS2 version was a downgrade, imo) is still my favorite from that series.
Fight Night really didn't get good till Round 4. If I didn't play literally hundreds of hours with Victorious Boxers I probably would have been more positive with Fight Night but it felt like they weren't trying to make a sim and the head dude behind the series clearly was a boxing fan.
I would gladly take a sim like boxing game with fictional characters with a deep create a boxer mode