Who wins this epic war of power punching KO'ing mayhem between these lightheavy weight fighters?

I believe Sergey wins, high difficulty though. Stevenson has been stopped before by a guy who doesnt hit nowhere near as hard as Sergey. Of course Stevenson has the better win of the two's best wins ( Dawson/Campillo). I think Stevenson hits hard enough to earn his respect early but Kovalev is skilled enough to go to the body and then head to break down Superman.

Kovalev TKO 10

Who you pick?