“Per Patrick Saunders of the Denver Post, Halvorsen threw a 103.3 mph pitch in the ninth inning, which is the fastest of the Statcast era, with data going back to 2015.” — Matt Postins, SB Nation
Data on the Baseball Savant website confirmed that on 3 July, his 4-seam fastball was 103.3 MPH. Victor Caratini hit that pitch for a fly ball single. His previous record (102.9 MPH) was on 17 May against Pavin Smith. Smith hit that pitch for a ground ball out.
Let’s look at the velocities of Diamondbacks pitchers.