Harris, whose contract was purchased from Triple-A Memphis, takes the roster spot of outfielder Peter Bourjos, who was placed on paternity leave as he and his wife, Ashley, are expecting their first child. Harris tweeted the news out on Monday evening.
Harris rejoined the Cardinals' organization in February 2013, after filling his mandatory service time in the Navy, during which he sailed aboard the USS Ponce in the Persian Gulf, conducted drug stings in South America and served on diplomatic assignment in Russia.
But Harris, a 13th-round pick in the 2008 First-Year Player Draft, returned hardly in baseball form. With a fastball velocity hovering around 80 mph when he reported to his first Spring Training, Harris wondered if the Cardinals would even want him. But the organization gave him a chance and watched as Harris slowly started to more closely resemble the kid they once scouted.
Harris posted a 0.81 ERA that summer with the short-season club in State College. He then climbed three levels in 2014, setting himself up to be a non-roster invitee in Spring Training this year. There, Harris impressed with his cutter, split-finger fastball and improving breaking ball. His velocity has crept back up to the low-90s, and he allowed only two runs on three hits in 9 2/3 Grapefruit League innings.
He was pegged as the Triple-A closer to begin this season and notched two saves in four appearances before getting the set of orders he has long waited for.
When Harris makes his debut, he'll become the first graduate of the Naval Academy in 94 years to appear in a Major League game.
Jenifer Langosch is a reporter for MLB.com. Read her blog, By Gosh, It's Langosch, follow her on Twitter @LangoschMLB and like her Facebook page Jenifer Langosch for Cardinals.com. This story was not subject to the approval of Major League Baseball or its clubs.