It's also possible, though, that the O's already made their major relief acquisition. That would be Logan Verrett, the one-time Rule 5 pick by Baltimore who the team just acquired from the Mets for cash considerations. Having Verrett in the fold, along with long-relief, team-controlled types like Tyler Wilson, Mike Wright, Parker Bridwell, and T.J. McFarland, made Vance Worley (and his potential arbitration raise to over $3 million) expendable (RIP Vanimal mentions).
Still, despite having one of the very best left-handed relievers in baseball in Zach Britton, the O's always seem to be in search of another southpaw relief option. The rest of the team's best relievers pitch from the right side, and the ineffective Brian Matusz is gone. Besides Britton, the only other left-handed relievers on the 40-man roster are Donnie Hart, McFarland, and Jayson Aquino. And that's why left-handed reliever always seems to be mentioned as a possibility for the Orioles in free agency. But not only does that seem like a luxury the O's can't really afford right now, it may also not be one the team needs.
Almost every bullpen could use another good reliever, but it helps when you don't have to find those guys in free agency. The relief market has shifted back in many of those pitchers' favor. Did you have an opinion on Brett Cecil? Pretty good left-hander, right, but certainly not amazing. Well, Cecil will be making more than $7 million in each of the next four seasons. That's not top closer money, but that's still a lot. The Orioles should know; they handed a similar contract to Darren O'Day.
Hart in all probability won't be the next O'Day or Cecil type, but he did excel last season in the one area the O's needed him to: retiring opposing lefties. Hart didn't make his major league debut until the middle of July, and he only pitched 18 1/3 innings. If you just look at his ERA (0.49), he had tremendous success. A low ERA is nice to have, of course, but obviously there's more to it than that. Hart struck out less than six batters per nine innings and posted a BABIP of just .212. Certainly a 0.49 ERA in limited duty would look even better alongside a high strikeout rate, but maybe that's being greedy.
Let's look at some splits data. Thirteen of Hart's innings came against lefties, and he was tremendous against them. Again, he was brought up to get lefties out, and he did. Left-handers combined for a batting line of only .122/.190/.158 (.163 wOBA) against him. Just one left-handed batter earned an extra-base hit against him. Against lefties, Hart posted a strikeout percentage of 25%. Against right-handed batters, that number was under 4%.
Hart also induced plenty of weak contact against lefties. Of all pitchers who threw at least 10 innings against left-handed batters last season (yes, I know 10 innings is not a huge sample), only one pitcher had a lower wOBA against: Clayton Kershaw (.137). Hart placed fourth in the lowest amount of hard contact allowed (13.3%); Britton finished first in that department (10.3%). On contact that qualified as soft, Hart tied for 11th (33.3%).
None of the above is proof that Hart will be able to continue his limited sample size dominance. Maybe left-handers will adjust to his funky delivery and sinker/slider combination the more he pitches.
But that's easier than it sounds.
Hart will be asked to face some right-handers, and he may struggle in that department. But as long as he can keep retiring lefties at a decent clip, he'll have a spot in the bullpen. The best part of that: Hart makes the league minimum. Someone like lefty Boone Logan, who has been loosely attached to the Orioles, recently completed a three-year, $16.5 million deal with the Rockies and will be looking for another payday over multiple years. He's much more proven than someone like Hart, but if the Orioles have someone who can do close to what Logan can do for a whole lot less, that's a real bonus. Even Marc Rzepcynski just signed a contract with the Mariners for two years and $11 million.
Dan Duquette has enough to do with not much payroll leeway without having to worry about adding a moderately priced reliever. Hopefully Hart's 2016 debut was a precursor of more supremacy over lefties.