It’s not unusual to open a new can of balls and find that the balls are less than perfect. In many instances, all three balls are slightly dead or completely dead.

Having sold tennis balls for 35 years, I can tell you that the pressure leak in the cans occurs in shipping.

Somebody drops the case of balls on it’s corner or opens the cardboard carton with a box cutter and nicks a can inside.

The shelf life of a can of balls is probably about three years; after that even perfectly-packaged cans leak pressure.

If you get a bad can, don’t use the balls; take the can back to your retailer and get them replaced. Dealers don’t like it when you use the balls ; then they can’t get credit from the ball manufacturer.

By the way, one of my new students asked me why balls don’t last longer. Good question. I told her: “Balls are like your tennis instructor; as they age they get softer and go bald.”

Gary Sherby is tennis director at Racquets and Togs Tennis Center, 115 Bradford St., just off the downtown square. His tennis tips appear Sundays.