Handling the Serve
The serve is one shot that you cannot affect; all you can do is to react to the ball. The problem with big serves is that you don't have enough time to take your normal swing to return the ball. If that's the case with your return of serve, try blocking the serve back.
I play a lot of big servers who force me to block back their first serves. As long as I can keep the ball deep when I block it back, I can still be in the point. What you have to watch out for with this method is not to get lazy and just block the ball down the middle of the court every time.
A good player will recognize this and sneak into the net after the serve and put away an easy volley off of your weak return. Try to block the ball with a purpose if you can. If you can block the ball to their backhand or down the line it's probably a safer play than just blocking it back down the middle.
If you have to swing at the return, make sure you take small backswings to give you enough time. By the time you take a large backswing, the ball could already be past you.
Racquet Prep
It helps to bring the racquet back sooner than you normally would to hit the ball. This reduces the feeling of being rushed to hit your shots. If you bring your racquet back sooner, you'll feel like you have more time to react to the ball. As soon as you see which side the ball is coming to get your racquet back to that side immediately.
If you have to block back some of your ground strokes, I say go for it. Sometimes your opponent can hit the ball so hard it's all you can do.
Against big hitters, sometimes the best strategy is just get the ball back over the net. Just because your opponent hit two big shots in a row doesn't mean they can hit three. A lot of big hitters get impatient and go for too much too early or simply aren't consistent enough and will miss after 1 or 2 shots. Put the ball back in the court and see what happens. Don't be afraid to lob if you have to. If your opponent hits the ball too hard for you to handle, throw up a deep lob to stay in the point.
All of these strategies are hard to do when your opponent is blasting balls. Be patient, and work the point to your advantage. Take the big power hitters out of their power zone with spin, placement and most importantly patience.
Make sure you do whatever you have to do to hit the ball back over the net. It can be tempting to try to match the power of your opponent. But try to resist; it can cost you the match if it's not your typical style of play.
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