Ground Ball Rate
Also known as: GB%, grounder rate
Ground ball rate (GB%) is the percentage of batted balls that are grounders — typically a negative indicator for power hitters, though contact hitters may use it strategically.
Grounders result from launch angles below 0° (negative angle). They rarely reach the outfield and are among the lowest-value batted-ball types per expected batting average. High ground ball rates for hitters usually indicate a steep or down-and-around barrel path, rollover tendencies, or late pitch recognition leading to pulled-side weak contact. Elite contact hitters in spacious parks may intentionally aim for the gap between infielders, but for most hitters a high GB% signals a path fault. The average professional ground ball rate sits around 44%; under 40% is considered a good hitter profile for power players.
Example
His 51% ground ball rate pointed to a top-hand rollover problem confirmed on film — his barrel was arriving at an 8° down angle on average.
Related terms
- Rolling OverRolling over is a swing fault where the top hand rotates over the bottom hand too early, closing the barrel through contact and producing weak grounders to the pull side.
- Line Drive RateLine drive rate (LD%) is the percentage of batted balls classified as line drives (typically 0–25° launch angle with hard contact) — the batted-ball type with the highest expected batting average.
- Launch Angle (Batting)Launch angle in batting is the vertical angle the ball leaves the bat. Roughly 10–25° produces the hardest, most productive contact.
- Attack Angle (Batting)Attack angle in batting is the vertical angle of the bat path through the hitting zone. A slightly upward attack angle (+5° to +15°) matches the pitch plane for hard contact.
- Barrel PathBarrel path is the trajectory the barrel of the bat travels through the hitting zone — matching it to the pitch plane for as long as possible maximises the chance of hard contact.
Related guides & benchmarks
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