The Athletics will promote top pitching prospect Sean Manaea to start on Friday, Susan Slusser of the San Francisco Chronicle reports. Manaea, a 24-year-old southpaw, came to Oakland last summer in the deal that sent Ben Zobrist to the Royals.

Since his arrival, Manaea has done nothing but impress. Already considered a top-100 prospect, he dominated at Double-A and started out the 2016 season at the highest level of the minors. Over 18 innings in three starts, he owns a 1.50 ERA with 10.5 K/9 against 2.0 BB/9.

Entering the year, Baseball America credited Manaea’s big fastball, inconsistent but intriguing slider, and promising but still-developing change. BA rated him just inside the top fifty pre-MLB assets in the game, while MLB.com (#65) and ESPN.com’s Keith Law (#59) placed him a bit further down on their own lists. He isn’t generally seen as a fully-finished product, with polish on the secondary offerings and command cited as areas for improvement, but he’s certainly has done enough to warrant a shot at the major league level.

Righty Jesse Hahn had seemed in line for a promotion as the club looks to replace the optioned Eric Surkamp, and he’s certainly the more experienced arm. But as Slusser explains, Hahn is dealing with a blister at present so wasn’t an immediate option.

Whether or not Manaea will get more than a spot start remains to be seen. Either way, he won’t have the chance to accumulate enough MLB time to achieve a full year of service. But if Manaea can stick at the major league level, he would line himself up for future Super Two status and an extra year of arbitration eligibility.

The young lefty is one of several notable arms to get their first call-ups in recent days. You can read up on all of the recent top prospect promotions right here.