The 30-year-old Harris spent the season on the 60-day disabled list. The Cards had hoped that he could return from Tommy John surgery in June 2015 to make an impact on the roster this season, but Harris didn’t end up pitching in the Majors or minors this year. The Naval Academy product made his MLB debut last season and tossed 27 innings of 3.67 ERA ball with 5.0 K/9, 4.3 BB/9 and a 45.1 percent ground-ball rate. In addition to the 27 frames he compiled in 2015, Harris has a 2.92 ERA with 7.2 K/9 against 3.4 BB/9 in his minor league career.
Rosario, 29, made his MLB debut this season, hitting .184/.225/.237 over the life of 41 plate appearances. He’s never hit all that much, as evidenced by his .253/.302/.327 line in parts of five Triple-A seasons, though he’s caught 42 percent of attempted base-stealers throughout his 11-year minor league career.
Ohlman, 25, is a former Orioles farmhand that spent his second season with the Cardinals organization in 2016. The 25-year-old split the 2016 season between Double-A and Triple-A, where he batted a combined .287/.344/.434. Ohlman saw 54 games/186 plate appearances at the Triple-A level this year — his first exposure to that level of competition — and fared well with the bat, hitting .280/.333/.464.