Sacha gave away the match..I wish Rafa would reach out to Feli Lopez to work with him on his service..
Sasha just turned 24, not over the hill but a tad beyond being a prodigious wonderkind.. Physically he has all the tools and that serve when it’s on lifts his whole game to an impressive level. It’s a natural motion for Sasha , mechanically very sound.
Rafa on the other hand has always tinkered/tweaked with his serve and while it’s been very effective at times, the serve was IMO never a nice fluid motion , as a youngster it was almost an afterthought. He’s “willed” himself into being a better server , but it’s not natural so it can and will breakdown at times, to which Rafa trudges on and goes back to the drawing board. The anti-Feliciano Lopez So to speak.
In contrast, with his height and feel Zeverev should have an ease with his serve, it’s not an “add on”.
The difference is all mental, Rafa even while struggling with the serve has never developed full blown yips, and for someone as relatively young as Zverev, it’s hard to shake that mental albatross he’s hung on himself.