This is pretty incredible.
The Giants homered four times in one inning for the first time since 2011 last week, in a wild game vs. the White Sox where they hit a total of seven long balls. All four home runs in the fifth inning came at the expense of Michael Kopech, who was eventually pulled after giving up the fourth blast to David Villar.
Now a video by baseball video analyzer extraordinaire Jomboy appears to have uncovered that Kopech’s issue went beyond not having his best stuff. The above video illustrates that Kopech was tipping his pitches by changing his glove positioning when he was throwing curveballs.
When Kopech was throwing the curveball, his glove would flare up. When he was throwing his other pitches, the glove would remain flat on his wrist. Once they identified the tell, you can see Giants hitters staring directly at Kopech’s glove has he got set to throw.
Two of the home runs came via the curveball and two came via the fastball. It looked like pitchers were sitting on the pitches they wanted to hit, and then waited for the tip to know when to swing. Joc Pederson also homered off Kopech in the second inning on a fastball.
Considering the subtlety of the tell, it’s a pretty incredible discovery by the Giants, who basically broke the game open by being observant about their opponent. In addition, the Giants hitters also deserve credit for hitting the balls out even if they knew what was coming. Overall, it’s good for Kopech too, who can now clean up a serious issue.