Quick answer: Down-the-line: from the top, the hands and club move outward (toward the ball line) before dropping; the club crosses the plane and attacks out-to-in.
What it does to the ball
Out-to-in path: a pull if the face matches the path and a slice if it stays open to it (the curve is set by the face-to-path difference); divots pointing left.
Root causes (by frequency)
Starting the downswing with the shoulders and arms instead of the hips
An open face the player compensates for by throwing the club outside
Too much aggression from the trail side
How to fix it
Let the hands drop straight down to start the downswing while the hips rotate: the club must come down inside the path it went up on
Drills that fix it
The outside guardian · 15 min · 20 reps
Force the downswing to arrive from the inside Place a headcover 5 cm outside and 10 cm behind the ball. Hit balls without touching it: if you come over the top, you'll strike it before the ball. Start with an 8-iron at 60% and raise the intensity gradually.
Transition pump · 15 min · 12 reps
Groove the move of dropping the club to the inside Swing to the top and make two rehearsal pumps down to hip height, letting the hands drop straight down while the hips rotate; on the third, hit the ball. The club should feel behind your back, never above your shoulders.
Frequently asked questions
What is "Over the top (downswing from outside)" in the golf swing?
Down-the-line: from the top, the hands and club move outward (toward the ball line) before dropping; the club crosses the plane and attacks out-to-in.
What does over the top (downswing from outside) do to the ball?
Out-to-in path: a pull if the face matches the path and a slice if it stays open to it (the curve is set by the face-to-path difference); divots pointing left.
How do you fix over the top (downswing from outside)?
Let the hands drop straight down to start the downswing while the hips rotate: the club must come down inside the path it went up on