Swing selection – Fastballs

You can’t hit a home run without swinging. Swing is so important for a batter and choosing a right pitch to swing is indeed necessary. Thus, swing selection is a key lesson for a batter. In the 2020 season, the Baltimore Orioles had a swing rate of 50.4%, leading the majors. In the National League, the Mets’ swing rate was 48.8%, leading the NL. In the meantime, the Red Sox and the Rockies each had a swing rate of 48.5%. However, some teams were not that aggressive at swinging. The Padres, the Cardinals and the Mariners each had a swing rate of 43.6%. The Yankees’ swing rate was 43.3% and the Angels only had a swing rate of 42.8%.

In the 2020 season, which team did like to swing at fastballs? Firstly, let’s start with the most common pitch in baseball, 4-seam fastball. The Rockies batters swung at 4-seamers 1641 times and it was 18.6% of total pitches. Of these 1641 times, 1304 swings were in zone. The outcome of all these swings wasn’t bad and the Rockies batters had a batting average of .313 when they decided to swing at 4-seamers. The Cardinals only played 58 games last season and they swung 1215 times at 4-seamers. The Angels had the lowest swing rate last season and they only swung at 4-seamers 1255 times and it was 13.8% of total pitches. Secondly, let’s loot at sinker. The Atlanta Braves swung at sinkers 808 times and it was 8.7% of total pitches. Of these 808 swings, 582 times were in zone. The Braves were good at hitting sinkers last season and they had a batting average of .350 while swinging at sinkers. Pitchers have to be careful to throw a sinker against the Braves batters. The Dodgers and the A’s each swung at sinkers 531 times. The Mariners only swung at sinkers 522 times. It seemed that throwing a sinker wasn’t a great idea in the big league. Batters posted a batting average of .286 against sinkers. Mariano Rivera’s cutter was one of the most devastating pitches in the MLB. However, it’s not that easy to throw a dominant cutter. Hence, we don’t see many pitchers who frequently throw cutters. Meanwhile, hitters have to be cautious once they swing at cutters. The Phillies hitter loved to swing at cutters last season, swinging 392 times. Of these 392 swings, 288 times were in zone. The result of swinging at cutters was ok for the Phillies since the batting average was .261 and xwOBA was .275 while swinging at cutters. The Mariners only swung 170 times against cutters and the batting average was .241. The league batting average against cutter was .256 in the 2020 season.

2020	4-seamer	Sinker	Cutter
Swings	41,442	18,850	8,679
Zone Swings	32,445	13,846	6,058
Zone Swings/Swings	78.3%	73.5%	69.8%

It’s not a surprise to see that major leaguers swung more at four-seamers last season and it’s quite reasonable to swing at a four-seamer in zone. We can see that more than 78% of these swings were in zone. Against sinkers, major league hitters swung nearly 19000 times last and 73.5% of these swings were in zone. However, less than 70% of swings were in zone when hitters swung at cutters. Late movement probably made it hard for hitters to read whether the pitch would be in zone or not.