Baseball players take batting slumps as a matter of course, while a tennis player who can't find the old groove thinks about switching to golf. All of us suffer through an occassional bad day. Hangovers, annoying injuries and everyday work stress have all been known to take the zip out of a cannonball serve, the sting out of a forehand volley. But when a bad day turns into a series of inexplicable losses, it's time to get help. Here are some suggestions:

CHANGE YOUR SCENERY: Find a new place to play. Try out a new surface, one that forces you to make adjustments. Get yourself invited to a club with a different atmosphere. Having to focus on new surroundings will take your mind off your tennis woes.

FIND A NEW PARTNER: If you're finding it difficult to stay awake against your regular competition, try a new opponent - especially one who's better and will force you to play your best. With your reputation on the line you'll find yourself scurrying about the court like the player of yesteryear.

TAKE A LESSON: All tennis pros have experienced slumps, and will sympathize with your problem. Go to the lesson with an open mind. Ask for a complete rundown of your game, specific and general. Have your pro write down his suggestions.

TRY A NEW GAME PLAN: This is an excellent opportunity to work on your serve and volley game and that topspin backhand. Experimenting with new strokes and strategies will take your mind off the negative aspects of your game. Just remember that you won't prove anything by overdoing it - i.e , rushing the net behind everything, or hitting nothing but topspin. Be innovative with a plan. After all, you have nothing to lose.

WATCH A PRO TOURNAMENT: If your slump hits while the pros are in town, head over to catch your favorites, live. This experience is guaranteed to pick up your game for at least a couple of days - perhaps long enough to break out of the doldrums.

PLAY IN A TOURNAMENT: Like a new partner, this is bound to stimulate your adrenaline. If you can't get too excited about club tournaments, try a city open. Better yet, play in an out-of-town tournament. To survive in any tournament you have to get psyched up. This is probably the best way to find out what's really right - and to

VARY YOUR PRACTICE ROUTINE: Dull, purposeless practice sessions can lead to uninspiring match play. Try some new drills: crosscourt, 3 out of 5 tie-breakers. Use your imagination to make practicing more fun.

TRY A NEW RACKET: It may not be the racket that ails you, but many a beleaguered tennis player has had his spirits lifted by the presence of a new weapon in his hands. You don't have to rush out and buy a $200 composite. Take out a loaner or ask to borrow your friend's coveted frame. Just make sure you don't blame it on the racket.

JOG YOUR MIND: You can't preclude the possibility that your problems are all mental. Tennis mind cluttered? Reread Gallwey's Inner Tennis to unthink and relax you game. Find out how today's stars cope with being over-tennised.

A SHORT LAYOFF: If you still can't get untracked, then you're entitled to a layoff. While top pros like Vilas and Soloman unwind from the circuit with a month's holiday, you can benefit from a week's vacation from the game. Swim, sail, fish or do anything unrelated to tennis. When you get back to the courts that fuzzy little ball will: seem like an old lost friend.