YOU figure it out.
NO serve to speak of. Lowest level ATP volleys. Forehand grip forehand volleys and 2hbh grip backhand volleys. Relies on his groundstrokes and return of serves to be No. ONE ATP for a couple years.
Was his groundstrokes considered "heavy"? He hit 50% topspin on his forehand side, the rest sidespin. He hit 50% topspin on his 2hbh, the rest a combination of UNDERspin and sidespin.
What about Rosewall? He hit mainly a combi of slice and sidespin, and he was a pretty good player, with no serve.