Tess Taruskin at FanGraphs did a really cool breakdown of Bobby Witt, Jr.’s first MLB hit, against Triston McKenzie (there are gifs at the link!):
The pitch Witt hit was a slider left above the strike zone. It’s a pitch that McKenzie has executed well in the past, using the breaking ball to just barely nick the upper corner of the zone before the batter has a chance to adjust to it.
the one he offered to Witt last Thursday was much flatter (just 23 inches of vertical movement), and had less spin and velocity.