This is probably the most commonly used serving tactic in tennis today. A player using this tactic employs a powerful two-shot combination of serve and groundstroke to outmanoeuvre and overpower an opponent. Ideally, the server chooses the serve that allows his/her favourite second shot (either a forehand or backhand) to be used as often as possible.
The serve and groundstroke attack tactic is often used effectively with a wide serve that forces the opponent out of the court. This serve creates a natural space for the server to hit their second shot into. Right-handed female players use this tactic particularly well from the deuce court (using the slice serve - see diagram 1), whereas right-handed male players tend to favour the wide serve from the advantage court (using topspin to outmanoeuvre the opponent - see diagram 2). Both of these serves allow an aggressive second shot to be hit either into the space or back behind the returner:

A more central return is expected when serving down the middle from both sides. If this is the case, encourage your players, whenever possible, to run around the backhand to hit an aggressive forehand. More angle can often be created with this shot, as well as the fact that it 'looks' more threatening!
Remember to encourage your players to use the back behind tactic if the returner recovers too quickly back into the court. This simply means hitting the second shot back in the direction in which the serve was hit. This wrong-footing tactic is used particularly well on clay courts where it is more difficult to change direction quickly.
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The serve and baseline control tactic requires the server to maintain control over an opponent for the duration of the rally. However, unlike the groundstroke attack tactic, there may not be an obvious second ball to hit - meaning that the server has to work harder and longer to win the point. This may be because the returner has returned deep down the middle (this provides no obvious space to hit the second shot into), or perhaps because the serve isn't strong enough to create an obvious attacking opportunity. Whatever the reason, the key factor when using this tactic is to carry a pre-planned mentality of not allowing the opponent to regain a neutral position in the point.
This is an important tactic for your players to learn since being able to repeat it will also allow them to develop the serve and groundstroke attack tactic. (See section 3 - both back - for more details on baseline tactics).
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We see less serve and volley tactics being used today because the strength of the return, passing shot, and lob has improved so much. Players are comfortable hitting these shots on the run and usually like a target to aim for at the net. However, many servers occasionally use this tactic as a way of mixing up the rhythm of play.
Generally, the serve and volley tactic is employed with a strong first serve hit down the middle of the court. This middle serve reduces the angles available to the returner (see Diagram 3). The serve out wide is used more on fast courts where the bounce is quick and the ball moves away from the returner's swing path - making it very hard to attack (see Diagram 4).

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Another tactic that involves the server finishing the point at the net is the serve and sneak tactic. This contrasts with the serve and volley tactic, in that the server makes the decision to approach or 'sneak' into the net after the serve has been hit, instead of before. Crucially, this allows the player to assess quickly the quality of the serve before deciding to come forwards. The server's second shot will usually be a drive volley, or smash, when playing against the high, floated return and a normal 'block' volley against the lower return. The key to this tactic is a player's ability to read the flight path of the return as quickly as possible. Doing this well creates intense time pressure on an opponent.
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