Pittsburgh Pirates: Joe Musgrove’s Slider is Becoming a Weapon

Despite being plagued by the long ball in his first two starts of the season, Joe Msugrove’s slider is becoming a weapon for the Pittsburgh Pirates.

Entering the 2020 season, expectations were high for Joe Musgrove. The right-handed pitcher was going to be looked upon to anchor the starting rotation for the Pittsburgh Pirates, and these expectations only grew after Chris Archer was lost for the season due to surgery.

Manager Derek Shelton showed a lot of faith in Musgrove when he named Musgrove the team’s Opening Day starter. Musgrove has now made two starts this season for the Pittsburgh Pirates. While he has been plagued by the home run ball in these starts, his slider has started to develop into a weapon.

Despite the four home runs he has allowed, Musgrove has limited opposing batters to 32.0% hard contact rate and an average exit velocity of 85.7 MPH. Both of these numbers are better than the MLB league average from 2019.

His four-seamed fastball is the pitch that has gotten Musgrove into trouble. Opposing batters are slugging .643 off the pitch. Two of the four home runs he has allowed have come when he threw the four-seamer.

In the off-season we discussed how 2020 could be a breakout season for Musgrove. A big reason for this belief was that new pitching coach Oscar Marin would have Musgrove throw his slider more. The early season results have only further solidified this belief.

We have already discussed Msugrove’s struggles with his fastball this season. As for his slider, the results have been the opposite. He has allowed just one hit, albeit a home run, off of his slider through his first two starts. He has generated a 66.7% whiff rate with the pitch, and the average exit velocity off of it has been just 83.7 MPH. As a point of reference, the MLB average for exit velocity is 88.1 MPH.

So far this season Msugrove has struck out 15 batters, eight of those strikeouts have come via the slider. His slider is averaging 41.8 inches of vertical drop and 13.7 inches of horizontal break. Both of which are better than average.

His slider has also had ridiculous spin rate on it this season. An average slider spin rate is 2400-2500 RPMs. Musgrove’s slider has been an RPM of 2656 so far this season, which among the best in baseball.

A good slider is nothing new for Musgrove. Last season opposing batters slugged just .240 off of his slider, to go with a 39.3% whiff rate and an 83.3 MPH exit velocity. The issue was he was not throwing the pitch enough.

In 2019 Musgrove threw his slider just 22.1% of the time, and this number spiked late in the season due to him throwing it more in his final eight starts of the season. Not coincidentally, this was the best eight start stretch of his career.

Through two starts this season, he has thrown the slider just 20.2% of the time. However, he has nearly doubled his curveball usage (9.5% to 17.4%) which is a big reason why he has not thrown the slider more.

That said, Msugrove should still look to increase his slider usage. He threw his slider on 25.% of his pitches against the Cardinals in his first start of the season. Throwing the pitch at least 25% of the time should be the norm for Musgrove in his outings.

So far this season Musgrove’s four-seamer usage has dropped from over 37% in 2019 to 32.6% this season. That is good to see. However, in an ideal world you would like to see his slider usage increase a few ticks. Musgrove’s slider is becoming a weapon, and now it is time to treat it as such.