As a key member of the Orioles concluded a minor-league rehab assignment, another is about to begin his.With starting pitcher Yovani Gallardo performing well in his third and final rehab start on Monday, shortstop J.J. Hardy will begin playing for Double-A Bowie on Tuesday as he moves closer to a return from a fractured left foot suffered on May 1. Gallardo could be activated from the 15-day disabled list to make Saturday’s start against the Toronto Blue Jays while it remains unclear how long Hardy’s assignment will last.Pitching for Triple-A Norfolk against Charlotte on Monday, Gallardo turned in a strong five-inning performance in which he allowed just one run on one hit while striking out five and issuing two walks. The lone run he allowed came on a leadoff homer before he settled in to throw 90 pitches.Showing better velocity than he did early in the season when he posted a 7.00 ERA in four starts before going on the DL with right shoulder tendinitis, Gallardo will be asked to help stabilize a starting rotation that’s struggled mightily in recent weeks. It remains unclear whose rotation spot Gallardo will take, but veteran Ubaldo Jimenez owns a grotesque 6.89 ERA and both Mike Wright and Tyler Wilson have minor-league options and have also struggled.Meanwhile, the Orioles are eager to welcome back Hardy to help solidify the left side of their infield. Gold Glove third baseman Manny Machado has played very well shifting to shortstop, but Baltimore has had problems at the hot corner with Ryan Flaherty and Paul Janish offering substandard offense and Pedro Alvarez providing subpar defense when asked to play there.Ideally, the Orioles would like to have Hardy return before Machado begins serving his suspension stemming from last week’s brawl with Yordano Ventura and the Kansas City Royals. Machado’s four-game suspension is pending an appeal.