The Mariners announced after Wednesday’s game that they will select Taijuan Walker from Class AAA Tacoma to start Friday against the Houston Astros. It will serve as the MLB debut for the right-handed pitcher.
The official roster move will be made Friday prior to the game.
Walker has long been one of the top pitching prospects in the organization, having been listed as the No. 5 prospect in baseball by MLB.com heading into this season. He has made 25 combined starts for the Rainers and Class AA Jackson with a 9-10 record, 2.93 ERA and 160 strikeouts (tied for fourth among minor leaguers this season).
In four minor league seasons, Walker has a 23-26 record, 3.46 ERA and 400 strikeouts.
Honors this year for Walker — who checks in at 6 foot 4, 210 pounds — include pitching in the All-Star Futures Game and being selected as a Southern League All-Star.
At 21 years, 17 days old on Friday, Walker will be the fifth-youngest in team history to debut as a starting pitcher. He will wear No. 27.
Corrected version: An earlier version of this post Wednesday incorrectly listed Walker with a 9.10 ERA. He has a 9-10 record and a 2.93 ERA. It was corrected shortly after being published.