Quick answer: Face-on: the lead hip slides laterally past the lead foot without rotating; the head dips toward the target.
What it does to the ball
The face arrives late relative to the body: blocks to the right, or sudden hooks when the hands catch up.
Root causes (by frequency)
Confusing the lateral bump with a continuous slide
Hips that won't rotate for lack of lead-side stability (TPI screen)
How to fix it
Short bump, then rotate: after a minimal shift, feel the lead hip turning back toward your lead heel
Drills that fix it
Lead-hip post · 15 min · 12 reps
Turn the slide into rotation after the initial bump Plant a rod or set your bag brushing the outside of your lead hip. Swing down with a short bump and rotate the hip back and behind you before touching the post. On face-on video, the lead hip must not slide past the lead foot.
Frequently asked questions
What is "Excessive hip slide in the downswing" in the golf swing?
Face-on: the lead hip slides laterally past the lead foot without rotating; the head dips toward the target.
What does excessive hip slide in the downswing do to the ball?
The face arrives late relative to the body: blocks to the right, or sudden hooks when the hands catch up.
How do you fix excessive hip slide in the downswing?
Short bump, then rotate: after a minimal shift, feel the lead hip turning back toward your lead heel
Sources
Titleist Performance Institute — Body-Swing Connection screening
Dr. Young-Hoo Kwon, Texas Woman's University — Golf Biomechanics Instructor Program (secuencia cinemática, plano funcional)