Hart is meeting up with the team in Boston and will join Richard Bleier as the only southpaw relief options for manager Buck Showalter. He basically is going to replace Nestor Cortes Jr., though it took a few other moves since the Orioles designated the Rule 5 pick for assignment.
The Orioles will continue to have an open spot on their 40-man roster after choosing Hart, who’s allowed one hit and struck out seven batters in 3 2/3 innings with Triple-A Norfolk.
Other possibilities included non-roster relievers Joely Rodriguez and Josh Edgin. However, the Orioles have turned to Hart, 27, who rode the shuttle between the majors and International League last summer and went 2-0 with a 3.71 ERA and 1.397 WHIP in 51 games with the Orioles.
Left-handers hit .273 against Hart last year, compared to the .132 average posted in 2016.
The Orioles optioned Hart in spring training after he allowed three runs and 10 hits, walked three batters and struck out 11 in eight innings.
A spot was cleared for Hart when the Orioles optioned Yefry Ramirez to Triple-A Norfolk following Wednesday night’s 5-3 win over the Blue Jays. Showalter said the club would call up a left-handed reliever.
Showalter wanted right-handers in long relief, including Hunter Harvey, based on the Blue Jays’ roster construction. But the Red Sox field more left-handed hitters, which makes Hart an important piece.
The Orioles are back to having a four-man bench after recalling utility infielder Engelb Vielma on Wednesday.