This story was excerpted from Martín Gallegos’ A’s Beat newsletter. To read the full newsletter, click here. And subscribe to get it regularly in your inbox.

Mason Miller made quite the electric Major League debut, impressing more than just those in his own dugout.

Miller, Oakland’s No. 3 prospect, had the full attention of his A’s teammates and coaches with each pitch that lit up the radar gun at the Coliseum on Wednesday. Equally impressed were the Cubs hitters that had to step in against the hard-throwing right-hander.

Patrick Wisdom had to deal with Miller’s fastball at its peak. During their showdown in the second inning, Miller fired fastballs of 102.3 mph and 102.5 mph, marking the two fastest pitches thrown by any A’s pitcher in the Statcast era. Frankie Montas previously held the fastest pitch thrown, which came in at 101.6 mph against the Mets in 2017.

Here’s what Wisdom had to say about Miller’s fastball:

“It was fast,” Wisdom said. “He’s got an electric heater. You have to make your decisions all that much quicker and get ready even earlier. He’s electric.”

“We see the video, we see the metrics and what he’s got, but until you’re in that box, you don’t really know for sure what it’s going to look like. You kind of use your first at-bat to gauge things.”

Cubs catcher Tucker Barnhart had rave reviews of Miller’s stuff, even offering his thoughts on the future potential of the 24-year-old.

“I think he’s got a really good chance to be pretty dang good,” Barnhart said. “He is a guy that throws a fastball that really, really gets on you. That’s obvious with the velocity, but with the metric side of things, it’s pretty special. He was landing breaking balls and throwing cutters into lefties. It was making it difficult to kind of commit to something out over the plate.

“In terms of experience, he’s young. I’m anxious to watch him grow as a player. As a player, you want guys in the league like that.”

On a pitch count of 80 in his first start, Miller will get a chance to build to a larger workload in his next outing, scheduled for Tuesday night against Shohei Ohtani, Mike Trout and the Angels at Angel Stadium.