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Advanced Stats by Pat - Vol. 5

It's been a hot minute since I blessed your eyes with nerd stats. I've yet to touch on Sweet Spot Percentage and Spin Rate, so here's a breakdown of both in this installment of:


Sweet Spot Percentage (SwSp%)

Sweet Spot Percentage is defined as “A batted ball event that produces a launch angle between 8 and 32 degrees”. These degrees produce the most amount of hits. Now you may be asking, “what’s the point of Barrel percentage if this is the same thing?”. Well, it’s not at all. Barrel percentage measures batted balls in play that have an expected batting average of .500 or more. Nested in Sweet Spot percentage are all of the recorded Barrels, but not the opposite. For example, the prime launch angle and exit velocity for a barrel is 95mph+ at 20 degrees. What about a double to the outfield gap that barely clears 8 degree launch angle? That’s not a barrel but does fall under the sweet spot percentage.

Sweet Spot percentage is important because this measurement can lead you to a batters effectiveness to put the bat on the ball. On the flip side, you can see how pitchers are delivering their pitches and see where their giving up the most contact.

Last year's SwSp% leaders were Dominic Smith (43%), Donovan Solano

(43.4%), and Freddie Freeman (49.2%). At the opposite end was Isiah Kiner-Falefa (22.2%), Adalberto Mondesi (19.9%), and Jonathan Villar (18.7%).

SwSp% also accounts for pitchers as well. In this case, the higher percentage means hitters batted balls against them were in that 8 to 32 degrees. Last year's leaders were Brandon Woodruff (26.1%), Shane Bieber (26.1%), and Trevor Bauer (25.9%). Pitchers that gave up the most Sweet Spot hits were Ryan Yarbrough (41.5%), Max Scherzer (41.9%), and Josh Lindblom (45%).


Active Spin AKA Spin Rate (SR)

The Exit Velocity comp for pitchers is Spin Rate. Simply put, it's how much the ball spins on it's way to the plate. Putting spin on a fastball increases it's effectiveness. When the fastball is thrown with a massive amount of backspin, the hitter sees the ball differently. When the pitch comes to the plate, it gives the illusion of the ball rising. While impossible given simple gravity rules, the hitter perceives the ball coming in lower than it actually is. What leads to this optical illusion is the aforementioned spin rate.

The more spin that is given to the fastball, the less it falls on it's way to the plate. Take the knuckleball, for example. This pitch is known for it's looping unpredictability going towards the hitter. In almost every knuckleball case, it dives hard at the end. This is because gravity has to work less on the ball to push it down. Now, the 12-6 Curve. The pitch gets it's name from the drop that the ball produces, going from 12 on a clock to 6, breaking vertically. Why does this pitch dip so hard? Pitchers throw this ball putting vertical spin on the ball. Combine this vertical spin with the effects of gravity, you get a pitch that slams into the dirt.

Spin Rate also helps out pitchers who don't throw as hard. A straight thrown 93mph fastball is basically batting practice to these hitters. The batter can clearly see the trajectory of the ball, so you can almost guarantee a hit on a pitch like that. Adding spin on the ball, meaning the pitcher snaps his wrist and almost drags his fingers off the seams as he releases the ball causes more spin. Almost half of the pitchers in the top 20 for fastball spin rate last year had fastball velocities under the league average of 94mph. As a matter of fact, three out of the top five pitchers in strikeouts last year all had fastball velocities under the league average (Bauer, Darvish, Bebier).

I couldn't grab the exact statistics on the spinniest (yes, I just made that word up) fastballs, so you can click this link for the full list from Statcast broken down by percentile rankings. Some notable names in the top ten were Darvish, Daniel Bard (welcome back), and the leader Trevor Bauer.


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