Score the second chance. A separate follow-up player anticipates the parry, reads where it drops, gets there first, and finishes the rebound with placement over power.
A shooter strikes from around twenty yards; the keeper is likely to parry rather than catch. A separate follower starts wide of the shooter and follows in for the rebound to finish. Read the keeper to anticipate the spill, and stay alert after every shot. Serve varied shots and rotate the shooter and follower.
Rebound goals are decided before the shot is taken. By the time a keeper parries, the ball is loose for perhaps a second, and nobody can cover ten yards in that time. Whoever scores was already moving while everyone else was watching the strike, which makes this a positioning habit rather than a finishing skill.
The habit is unglamorous and that is why it is rare. Following in a shot that will probably go in or probably go wide feels pointless, and a player does it twenty times for one goal. Coaches who want those goals have to make the run itself the thing that gets praised, because the reward rate is too low to sustain on its own.
Where to run is readable rather than random. Keepers parry to the sides far more often than they push balls straight back, because the natural hand position on a diving save deflects rather than blocks. A follow-up runner attacking the space wide of the keeper, slightly ahead of him, is covering the most likely outcome. Standing centrally behind the shooter covers the least likely one.
Reading the hands lets a player gamble early. A keeper going down with palms turned outwards is going to spill it wide; one who gets both hands behind it is going to hold.
The finish is a placement rather than a strike. Rebounds arrive at close range with the keeper on the floor and defenders converging, so accuracy and speed of contact beat power, and the target is usually the gap he has just vacated.
Save it to your private drills, then change the animation, adjust positions, swap equipment, or drop it into a session block. Or start from a blank pitch and build your own.