what about mc enroe,,,nastaste ,,,,bobby riggs.....   old good ones is ashe,,laver,,newcombe,,velas,,,borg,,,named a few

Federer is the greatest player ever. Johnny Mc couldn't hold his jock

It is almost impossible to compare tennis players from different generations.  They played with tiny wooden rackets 30 years ago and now they have these massive rackets that destroy the ball.  Mack also played against Borg, Connors, Ashe, Nastazi, Lendel etc.  That was the glory days of tennis.  Today's era doesn't seem to be as competitive.