The Oakland Athletics made a pair of roster moves ahead of their series-opening contest against the Texas Rangers on Monday: optioning struggling left-hander Jesús Luzardo to the minors and purchasing the contract of righty Domingo Acevedo. With due respect to Acevedo, Luzardo's demotion is the more notable of the transactions.

Luzardo, 23, had been expected to serve as one of the main members of Oakland's rotation. Alas, that hasn't come to fruition. Luzardo posted a 5.79 ERA and allowed 45 baserunners in 28 innings over six starts before fracturing his hand playing a video game. 

When Luzardo returned, about four weeks later, the A's moved him to the bullpen. His results haven't improved; instead, he's allowed more than a run (11) per inning pitched (10) over seven appearances. Luzardo has also yielded at least one home run in each of his last five outings.

Generally, struggling pitchers have one or two things working against them. It's difficult to find much that's working in Luzardo's favor. He's used four pitches more than 15 percent of the time this season, according to Statcast, and three of them have allowed a batting average of .296 or better. (The exception, his curveball, has held opponents to a .184 mark.) His strikeout rate has dipped, albeit barely, while his walk rate has increased alongside both his average and max exit velocities. Basically anything that can head in the wrong direction has so far this year for Luzardo.

It should be noted that while Luzardo's return to effectiveness is an important subplot for the A's -- for this year's purposes and the future -- they've received quality production from his successor in the rotation, rookie James Kaprielian. In seven outings, he's compiled a 2.84 ERA (142 ERA+) with a 2.47 strikeout-to-walk ratio. The A's originally acquired Kaprielian, who has missed his share of time because of injury, as part of the Sonny Gray trade with the New York Yankees back in July 2017.

The A's will enter play on Monday night with a 44-29 record, good for a tie with the Houston Astros for first place in the American League West.