Make it a three setters... it will spare you efforts. Ahaha
No, seriously. I played a five setter with a friend once. I recall that it didn't last five sets and that I lost.
I also recall that it was exhausting, long and that we were making stupid fatigue mistakes by the end.
A thing you will have to bother about is managing your energy. You'll have to play for at least 3 full sets,
for perhaps 30 to 45 minutes each... I mean, I wouldn't expect that match to end before 2 hours of play,
unless one of you is much better than the other or if you happen to play very fast tennis. With my friend,
sets generally lasted above 45 minutes, sometimes a full hour and it wasn't uncommon to play a tie break
or end a set 7-5. So, when you play and decide to go for a run to try and get back this pesky drop shot,
have a thought for how you'll be playing in two hours from then if you try to keep up the rhythm you
imposed over yourself.
When you get tired, moving becomes challenging, hard and, despite great will and desire, you're bound to
be slower as you play more and more points. Even if you're technically good, you'll make more mistakes
when you are tired than when you are fresh out of the warm-up before the match. Bending your knees,
moving forward, making small adjustment to ensure perfect spacing to the ball... all those details that
must be done with consistency and rigor to ensure quality shots will become a burden.
Here, on the other hand, you are somewhat "lucky": your friend is a big server and not a Nadal-like kind of
guy. A guy who has a physical edge will see the match fall on his side ever more as it lasts longer because
of what I explained above.
How do you play that sort of guy? Obviously, with 6 matches completed, you're better placed than any of
us to answer that question. Once of the usual response is to play with your slice if you have a good one.
Tall guys have a MUCH harder time digging low balls than small guys. Furthermore, since he's tall, you don't
have to bother about hitting arcs or flat strokes a lot: by his measure, arcing balls are much easier to strike!
So, if you're good at flattening out your balls, while keeping them in the lines a lot, it would be a good idea.
A second detail is that slices can be used, not only to force an opponent to bend and dig a low ball, it can
also be used to force him to work "vertically." A good way to exhaust an opponent is to force him to adapt
a lot: avoid, absolutely avoid, playing a pure "cost-to-coast" game. Forcing him to bend, move forward, move
backward... even better: with flat strokes and your slice, the change in speed risks to be very annoying,
even more than if you were arcing the balls more.
I wouldn't recommend doing the "chip and charge/ serve and volley" shortening scenario, unless you're very
good at it or unless your opponent is in much better shape than you are. If you can force him to work harder
than you, DO IT. For amateurs, a 5 setter is DAMN LONG and adjustments (the core and the corner stone of
tennis) happens to be the most tiring exercise during rallies... if you can just play two sets by forcing him to
do more adjustments than you (not necessarily by playing junk balls, but simply by varying the location of
your targets, the pace of your stroke and the type of spin), in the end it will pay big time.
Why? Even if you loose the one of these sets, you'll be in a better physical position to execute than he is
after both sets are completed. As time goes by, any bit of physical advantage, any bit of not being as tired
as the opponent, means more and more and more. In tennis, adjustments are big: your footwork and your
posture are important and being able to adjust better than your opponent for a set means winning the set.