The Phillies are designating right-hander Brian Keller for assignment, reports Robert Murray of FanSided. That’ll open the necessary 40-man roster spot to finalize their agreement with lefty Nestor Cortes Jr.

Keller is a 32-year-old organizational depth arm who made his MLB debut on July 25. He tossed three innings behind an opener in an appearance against the Yankees, allowing an Austin Wells home run but otherwise keeping a clean sheet. The Phillies optioned him a few days later.

Philadelphia signed Keller to a minor league contract in May. The University of Wisconsin-Milwaukee product hadn’t been in affiliated ball in four years. Keller had intended to pitch in Japan in the intervening seasons but essentially lost all three to injuries, including Tommy John surgery. Keller has done a decent job with Triple-A Lehigh Valley in his return to health, turning in a 3.86 ERA with a solid 23.2% strikeout rate and 9% walk percentage.

As one might expect for a pitcher with this late bloomer profile, Keller doesn’t have huge stuff. He averaged 92 mph on his fastball and leaned most heavily on a mid-80s cutter during his lone big league outing. The Phillies were clearly skeptical that repertoire would play over an extended run against MLB competition. Keller didn’t get much of a look despite their ongoing struggle to find a viable fifth starter.

Philadelphia will place the former 39th-round pick on waivers this week. He has a full slate of options, so another team could stash him in Triple-A if they’re willing to carry him on the 40-man roster. If Keller clears waivers, the Phils would keep him in the system on an outright assignment.