Who can call a let

With no umpire available, can either player call a let?

In a professional match, can players call a let when the umpire doesn't?

Hi Dale,

There are no official rules for when there is no umpire available.  However, usually both players can call a let in this situation.

In a professional match, only the umpire can call a let.  Sometimes the player will put their hand up to indicated to the umpire and their opponent that they thought it was a let but really the umpire has to call a let before the point stops.