This story was originally published on my website *
As the NC Dinos look to extend their control over the one-seed in the KBO playoff race, they turned to Drew Rucinski against the SK Wyverns and he delivered a strong performance. With just 91 pitches, Rucinski went seven innings, allowing just two runs, two hits, and two walks while striking out five as the Dinos pulled off a 9–5 win against the ninth-ranked Wyverns.
Rucinski has been consistently good for the Dinos over the last two seasons, posting a combined 3.10 ERA over 301.2 KBO innings, the ninth-best mark over the 2019–2020 seasons. In 2020, he’s sporting an ERA of 3.22 and FIP of 3.94, which is good but resides just outside of the top tier of starting pitchers in the KBO.
Rucinski wasn’t quite as sharp as he normally is, but he still pitched well against SK. For the 2020 season, Rucinski has been about average with a 64% strike% and an F-Strike% of 63%. Against SK, both those numbers were down, with his strike% just barely at 60% and an F-Strike% of just 54%. Interestingly, both those numbers dipped despite his whiff% of 24% against SK, a few percentage points higher than his 22% whiff rate on the season.
That’s likely due to his swing% falling from 48% on the season to just 41% against SK. These are lots of small differences but seem to indicate that Rucinski was struggling to locate his pitches more than usual, something I noticed while watching the game. He was throwing in the zone a lot less against right-handed hitters; against SK’s right-handed hitters, Rucinski threw 33% of his pitches in the “chase” zone on the edge of the plate, compared to just a 28% mark over his other starts this season, which came with a small reduction of pitches over the heart of the plate from 19.1% on the season to 17.8% against SK. Again, we’re still talking about really small samples in regards to this start, but this indicates that he was throwing more pitches that were not definite called strikes and that he wasn’t getting those calls. While his curveball and slider were above their season average on called strike%, his sinker has below average, and he didn’t get anything out of his tertiary pitches (his 4-seam and changeup).
Even though the umps might not have been giving Rucinski many favorable calls, he did a good job of handling things himself with the types of batted balls that he allowed. Over 17 batted balls, Rucinski allowed a hard-hit% of just 24% and a fly ball% of 29%. A majority of the balls that where hit were hit softly and either on the ground or for a pop-up. As a sinker heavy pitcher, that’s exactly what you want to see from Rucinski. He’s been really good at that all season, with his XBH% of 4.6% the third-lowest in the KBO with a minimum of 350 pitches tracked be me in the KBO Wizard.
In addition, despite his K/9 of 7.75, which is good, not great in the KBO, and a K/9 of 6.42 against SK, Rucinski sports one of the best swing and miss pitches in the KBO with his slider. Among pitches thrown 150+ times this season, his whiff% of 37% on his slider is the second-highest mark on the season. Rucinski usually throws it down and away from RHH and in the zone to LHH. From what I observed and comparing his location plots, that was the biggest difference in how “sharp” Rucinski appeared.
He didn’t throw his slider down and away nearly as often and tended to miss up against lefties, with four sliders missing up, accounting for 25% of the 16 sliders that have missed up in the zone, out of 190 total sliders. That was a consistent theme for Rucinski against SK; the two runs he gave up came off of a walk then HR when he hung a curveball in the middle of the plate to an LHH.
Overall, it was a fine start for Rucinski, throwing seven innings, allowing just four baserunners and two runs. He had a few issues with throwing strikes and his control, but compensated for them with his ability to induce weak contact and easily fielded outs by his defense.
*Stats from the KBO Wizard, myKBO.com, and FanGraphs.com*