By MATTHEW FUTTERMAN / THE ATHLETIC For five years, Alexander Zverev and Daniil Medvedev were the standard-bearers for the meat of the sandwich that men’s tennis had become for a generation of players born in the 1990s. In the first years of their careers, they had risen toward the top of the sport. In some ways, their combination of searing serves and counterpunching defense was revolutionary. Zverev and Medvedev dismantled one-dimensional big servers and tested Novak Djokovic, Rafael Nadal…
