On a ball that puts you in either an attacking or neutral position, your margin for error will be dictated by the quality of player that you are. However a 1-2m margin-for-error is generally a good goal to aim at when in complete control of your shot. This margin-for-error will increase when you're under pressure. Remember a player wins a match not by the amount of winners they hit, but by minimizing their unforced errors.
Be Consistent When You Attack
Play a consistent shot even when in an attacking situation.
Most players look to belt the ball especially when in an attacking situation. Instead of going for a winner when you have a short ball, focus on tactics one and two above, hitting to their weakness and coming in and playing a volley to the open court to win the point.
Don't be impatient and try to win the point a shot too early. This goes for any shot, including overhead smashes, a shot that is often missed because a player is going for too much off the shot. Instead play a smash with spin, so that you maintain control and look for accuracy and placement rather than purely power.
Focus on Depth
The deeper your shots become the better your overall game will be. A deep shot (as opposed to a ball that you hit short into the court) puts your opponent on their back-foot, takes time away from them and reduces the angle they can hit back into your court.
A player that is right at the net can have up to 180 degrees of court to hit into (when hovering over the net), while a player back at the baseline will generally only have an angle of between 20 to 30 degrees to hit into.
A player who hits a ball at the net will hit it back to you a lot quicker than someone at the baseline, therefore give yourself more time by pushing your opponent back behind the baseline with deep shots.
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