Since the ball is a sphere, is it possible that the ball’s actual contact with the court does not touch a line? From an overhead view the ball may appear to hit the line, but the ball’s width could be partly over the line and not actually touching it.
— Steve Thacher, Burke, VA
Tennis balls do compress when they strike the court and instant-replay systems take this into account. It’s technically possible for a shot to look good while barely missing the line. But unless your club is going to install Hawk-Eye, you need to call those shots good in
accordance with The Code, Item 6, which requires that you give your opponent the benefit of the doubt because “the game is much better played this way.”
Except where noted, answers are based on the ITF Rules of Tennis and USTA's The Code.
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