The changeup has always been a low usage pitch for DeSclafani having never been used more than 8% in his career. However, the usage split this year gets interesting when breaking it down by batter handedness: 10% against left-handed batters versus under 1% for the opposite side. Against lefties, he prefers throwing it in even counts or when the batter is ahead (11% each) compared to 6% in pitcher counts. The pitch did generate a very low batting average and wOBA, .180 and .204 respectively, which means the low usage of the pitch is not due to its lack of effectiveness but rather to him using it in very specific matchup situations.
DeSclafani’s curveball usage climbed back to where it was before the UCL injury that kept him away from the field in 2017, jumping from 4% last year to 15% this year. The injury may have made him more hesitant to use it last year as it sat at 80 mph. However, this year he saw that velocity climb to 83 mph and consequently saw its whiff% go from 24% to 39%. It was also his put-away pitch this year as it generated the most strikeouts of all his pitches at 46.
DeSclafani’s fastball can be broken down into two: the four-seamer at a 37% usage rate and the sinker at 18%. The choice of which one to use was dependent on batter handedness as it was split almost equally between both against lefties (28% for the four-seamer and 29% for the sinker) but favored the four-seamer against righties with 45% versus only 10% for the sinker. He throws them both at 94 mph, a 1 point increase for both compared to last year, but the sinker generates 5 extra inches of horizontal and vertical movements which helps keep the ball lower in the zone. This can be reflected by the sinker generating a 14% ground-ball rate compared to 5% for the four-seamer.
Just like his curveball, DeSclafani saw his slider gain 3 mph in velocity from last year which can again be attributed to last year being his first year back from the UCL injury. However, he was not able to get batters to swing and miss as much this year as its whiff rate dropped from 37% to 30% and consequently saw the strikeout rate drop from 32% to 19%. This can be explained by the pitch losing 7 inches of vertical movement since last season.
DeSclafani’s best pitch according to pVal in 2018 was his slider with an impressive 7.6 mark. It featured a strong 17.8% swinging-strike rate and held opponents to a .195 batting average against. He notably threw it more often in 2018 compared with previous years. Look for that to continue with the success it had
Averaging 93.5 mph this past season, DeSclafani’s four-seam fastball elicited a .354/.431/.698 batting line. An 86.5% contact rate against along with a 39% fly-ball rate led to home run issues as evidenced by a 26.3% HR/FB rate. All told, it was worth a -4.8 pVal.
Thrown 25.11% of the time in 2018, his two-seam fastball produced a -1.5 pVal. Opposing hitters were simply not fooled by the pitch as evidenced by the 92% contact rate against the pitch, which couldn’t be tamed by the 52.8% ground-ball rate of the pitch.The result was a .258 batting average against with the pitch along with a .398 slugging percentage.
The curveball was DeSclafani’s worst pitch in 2018 in terms of pVal with a poor -6.4 mark. It was reasonably successful outside the strike zone, but an 88.2% Z-contact rate on the pitch plus an unsightly 75% HR/FB rate led to a .438/.438/.1.188 batting line against the pitch.
DeSclafani’s least-used pitch in 2018 at 3.58% of the time, his changeup was not a great pitch for him. A poor 3.2% swinging-strike rate along with an elevated 25% HR/FB rate contributed to a rough .313/.353/.563 slash line against the pitch. The result was a -1.4 pVal.