Could also be that he misses fighting. His knee forced him out of boxing, not a missing desire to fight on.
Sergio is no mug, hes doing this because hes a boxer and misses comp..Just a little play around for him to get in reasonable shape for and look forward too. Two previous supreme talents just keeping the cogs oiled !
I heard the fight was a go then Chavez's hover round broke down and they couldn't find a wheel chair ramp long enough to go from the locker room to the ring!! lol