Many players are of the understanding that in order to hit the ball away from their opponent or to hit the ball to the opening in a match, they must hit the ball away from their practice partner. If you are practicing like this, soon you will be practicing by yourself. The whole purpose of practice is get high repetitions, a good rhythm with your strokes, get a good workout and practice targeting skills. Obviously, if you cannot hit the ball to a person in practice, then how can you hit it away from them in a match?
Go watch how the pros practice. You will see how long they can keep the ball in play. You will get much better timing and much better conditioning by practicing the correct way.
Remember, hit the ball to your practice partner, and hit it away from your opponent in a match.
Good luck on the courts!