The Backstory of MLB's "Juiced" Baseball
Visuals and statistics from the FiveThirtyEight article
Why did the "Juiced Ball"
Viewership + Excitement
- The MLB is in the midst of a 12-year decline in annual overall attendance and and saw TV ratings shrink -- until 2019.
- The home run is one of the most exciting aspects of the game, and fans tune in to watch them.
1, 4, 5
Ratings and Financial Gains
- Pitchers were dominating the sport in 2014 and many speculate that the ball was changed to accommodate to help batters.
- The 2019 MLB season featured increased TV and digital viewership and growing participation in baseball and softball.
- League revenue topped $10 billion in 2018 and is up more than 70 percent from a decade ago in 2019.
Changes in MLB Pitch Repertoire
- Higher fastball usage has resulted in more home runs in 2019 comparatively to 2017 and 2018, especially among those with <150 innings pitched (Starters).(11.8% ↑ between 2017 and 2019)
- The curve ball and sinker are the only two pitches with consistently less home runs hit against them the more frequently they are pitched.
(More Curveball = ↓ 7.7% HRs, More Sinker = ↓ 6.5% Hrs)
- Curve ball and sinker saw less usage among pitchers with 150+ innings (Starters)
(Curve = ↓ 1.49%, Sinker = ↓ 5.25%) while fastball usage has gone up (Fastball = ↑ 2.23%)
- Slider (↑2.72%) and changeup (↑1.71%) usage up among pitchers with <150 innings pitched (Non-starters).
- There has been an increase in average breaking balls and off speed pitches to batters with more than 250 plate appearances in a season.(Breaking:↑ 3.79%, Off speed:↑ 6.70%)
- Batters with more than 250 PAs averaged 18.56 HRs in 2019, ↑ 2.84 HRs/player from the previous year
- Batters with more than 250 PAs are increasing their home run percentage most against the fastball. (66.1 fastballs/HR in 2017 and 57.7 fastballs/HR in 2019, a change of 15.6%)
Pitcher & Batter Adjustments
Juiced Ball Era
Pitch Type Faced by MLB Batters (2017-2019)
1. Allentuck, D., & Draper, K. (2019, September 29). Baseball Saw a Million More Empty Seats. Does It Matter? Retrieved from
2. Arthur, R., & Dix, T. (2018, March 1). We X-Rayed Some MLB Baseballs. Here's What We Found. Retrieved from
3. Baseball Savant: Trending MLB Players, Statcast and Visualizations. (n.d.). Retrieved from
4. MLB sees fan growth across the board in 2019. (2019, September 30). Retrieved from
5. Moran, E. (2019, October 7). Another Year Of Declining Attendance: How Worried Should MLB Be? Retrieved from
6. Rymer, Z. D. (2019, May 3). MLB Should Fully Embrace Its Growing Juiced Ball 'Problem'. Retrieved from