Which shot seems to be the more solid? If you hit a deep ball is your opponent moving back to hit it or taking it on the rise?
At this point the smart tennis player should already be formulating an initial match strategy.
Now watch your opponent at the net . Are the volleys solid or are they popping up? Do they tend to float long or are they drop volleys. If your opponent doesn't look like a good volleyer there's a good bet that he's a baseliner who doesn't like to come to net.
Now look at the overhead. Again does it look solid with a good shoulder turn and a lot of power? Can your opponent smash to all parts of the court or does he tend to always hit the smash to the same place. If he smashes to the same place make a note and if you throw up a lob in the match anticipate that it will go the same place as in the warmup.
Some players don't even bother to hit overheads in the warmup so you know they won't be approaching the net very often if at all.
Continuing with tennis tip #1 - Now watch the serve. Does it look like it will give you trouble? Is it flat, slice ,or topspin? Does your opponent have more than one type of serve? Can he hit his serve to both sides of the service box?
And finally watch your opponent's return? Does it look like he can handle your serve? Is he ripping returns or just blocking. Are the returns floating? What side looks stronger?
All of this takes 5 minutes and at the end of the warmup the smart tennis player has a good idea of what he is going to try to do in the match.
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