Most players have specific serves they use when the match gets close or if it is an important point. A lot of lefthanders tend to hit their serve wide to the ad side with slice. Many right handers with a good kick serve tend to hit their serve wide to the ad side as well, sometimes even on their first serve.
Whatever the tendency, adjust your return of serve position to make the opponent hit the ball somewhere that is not as comfortable for them. I often stood with both feet in the doubles alley against players who liked to use their wide serve a lot.
Another good tactic is to take a step or two towards the anticipated serve as your opponent tosses the ball. This also works very well against players who like to serve into the body. Make sure you have gotten to your split step prior to the server's point of contact so you still have a good chance of reacting if the serve goes to a spot you were not expecting.
By taking away your opponent's best serve you can affect their ability to control the point and also make them less confident overall when they are serving.
Steve Annacone, USPTA Elite Pro, is the Director of Annacone Tennis (http://www.annaconetennis.com) and MyHamptonsPro based in Sag Harbor, NY (http://www. myhamptonspro.com) and Tennis Professional at Ventana Canyon Golf and Racquet Club in Tucson, AZ. For details on lessons, clinics, or coaching, contact Steve at firstname.lastname@example.org or call 865-300-7323