No skill to beat
I did beat hard. I just waited for him to charge me, then jumped right before he did, and pushed right as I was coming down. we bounced off each other until a bomb dropped and killed him before I died. Not really that difficult.
More of a chance that he dies before you, since they either both get hit or the red guy gets hit then takes 5 seconds to fall out.
Another way to win: take the explosion. you heard me. be on the same side as your opponent, and get blown up. somehow, your speed is transferred to the other guy and he'll fall off. On hard he's actually stupid enough to try to grab you out of the air and will kill himself half the time.