Minnesota Twins third baseman Josh Donaldson sparked some controversy this week by calling out Lucas Giolito over his alleged use of foreign substances. Giolito wasn’t happy, but the numbers seem to back Donaldson up.
Donaldson was heard saying “it’s not sticky anymore” after homering off Giolito on Tuesday. The Chicago White Sox pitcher was highly critical of Donaldson after learning of the comment, but the Twins third baseman only doubled down on his criticism the next day.
On Sunday, Giolito made his first start since his spat with Donaldson. The numbers certainly backed Donaldson: Giolito gave up a season-high 10 hits to the Detroit Tigers in only five innings, as his team lost 6-5. Giolito gave up all six of the team’s runs as well.
It’s not just the poor result that will raise eyebrows. According to MLB Statcast data, Giolito’s spin rate was down across the board from his season averages. Notably, he essentially shelved his curveball, and the only one he threw was down RPMs from his season average.
paging Josh Donaldson for comment on Giolito's spin rate today pic.twitter.com/qhVWCP9fXJ
— Listen Here Baseball Commissioner (@spacemnkymafia) July 4, 2021
The change in spin rate was particularly notable when compared to Giolito’s last start prior to MLB’s June 3 announcement of its planned enforcement measures.
Lucas Giolito's fastball spin rate was down 10% from his last pre-controversy start (May 30) and his slider was down 15%.
He allowed six runs on a season-high 10 hits in five innings.
— Dave Hogg (@stareagle) July 4, 2021
No, this doesn’t necessarily prove that Giolito had been using foreign substances. However, the data is pretty clear that something changed to cause less spin on Giolito’s pitches in the last month, and it’s probably not coincidence that it happened after MLB decided to aggressively enforce its rules against foreign substances. Donaldson seems to have the facts in his favor on this one.
It’s worth noting that Giolito is far from the only top pitcher facing questions about spin rate and foreign substances.
