To get the maximum flight a ball must be thrown as:

If a ball is moving from left to right and also spinning about a horizontal axis in anticlockwise wise direction about a horizontal axis perpendicular to the direction of motion then relative to the ball air will be moving from right to left. The resultant velocity of air above the ball will be (v+rω) while below it (v - rω). So in accordance with Bernoulli's principle, pressure above the ball will be less than below it. Due to this difference of pressure an upward force will act on the ball and hence the ball will deviate from its usual path OA0 and will hit the ground at A1, following path OA1 i.e., if a ball is thrown with back spin the pitch will curve less sharply prolonging the flight.