Detroit Tigers right-hander Casey Mize, the No. 1 pick in the 2018 MLB draft and one of the best prospects in baseball, has been placed on the Double-A injured list with shoulder inflammation, the team announced Friday. The official diagnosis is “minor posterior shoulder inflammation.”

Mize exited Thursday’s start with the trainer in the third inning after the catcher visited the mound and alerting the training staff his stuff had been down. Here’s video of Mize’s final pitch, reportedly a fastball in the mid-80s:

The good news: Mize’s injury appears to be minor. The bad news: Shoulder injuries are never good news. They can linger and reoccur, and evolve into something more serious. For now, it seems Mize will be good as new after some rest and rehab. The Tigers did not provide a timetable for his return. You can be sure they’ll be extra cautious with him.

In 13 starts at high Class A and Double-A this season, Mize owns a 0.92 ERA with a 0.69 WHIP and 75 strikeouts in 78 innings. He threw a no-hitter in his Double-A debut earlier this month. currently ranks Mize as the third-best prospect in baseball and the best pitching prospect overall. Here is a snippet of their scouting report:

With plus command and the ability to induce whiffs with three different pitches, Mize has the ingredients needed to headline a starting rotation. A plus-plus splitter in the mid-80s that dives at the plate is his best offering, and he’s adept at locating the pitch down in the zone or below it. Mize sets it up with a 92-97 mph fastball that he commands exceptionally well despite its running life. His mid-80s slider took a step forward as a junior, consistently grading as a plus offering, and he also has developed the ability to manipulate it into a harder cutter when he desires … With his plus stuff and plus command, it should surprise no one to see him move quickly through the Tigers’ system.

It should be noted Mize does have a history of arm issues. He missed time in 2017 with a flexor strain and general arm fatigue. Between college and pro ball, Mize threw 128 1/3 innings last season and was likely ticketed for 150 or so this year. He had a chance to make his MLB debut later this season and still could, though this shoulder injury may throw a wrench into things.