Four players total: one player at each corner of the court. Player A hits a groundstroke to Player B, landing the ball as close as possible to the sideline. Player B returns a groundstroke down the line to Player A.
Players C & D do the same on the opposite sideline.
After a few dozen hits, they can take a step or two in towards each other and continue at a shorter distance.
A tiebreak is a short sprint where every point is worth the same as a break of serve. The players who win them are rarely the ones who hit hardest. Here is how to coach the patterns, habits and scoreboard thinking that win the big points.
Most club players practise the serve on its own and then have no idea what to do with the ball that comes back. Serve plus one is the pattern that turns a good serve into a won point.
Wimbledon has just crowned another champion, and if you watched closely you saw the same thing every year: the best returners quietly won the tournament. Here is how to coach a return that pressures the server rather than just surviving it.