The next point - that's all you must think about.
When you have the opportunity, you strike.
The time your game is most vulnerable is when you're ahead; never let up.
Manners are manners. Jimmy Connors and Ilie Nastase have no respect. I don't want my kid seeing Nastase play. The demeanor you show on the court is important to tennis.... Maybe we (yesterday's stars) were too stereotyped. But we were told to behave or they'd take our racket away.
The roughest thing I ever said to an umpire was, 'Are you sure?'
An otherwise happily married couple may turn a mixed doubles game into a scene from Who's Afraid of Virginia Woolf.