Welcome to Over The Monster’s One Big Question series. For the next 40 (week)days, we will be trying to answer one important question for each player on the Red Sox 40-man roster. The goal is to find one interesting portion of each player’s game to watch for, whether that be in spring training or the early regular season. We’ll be going straight down the list on the team’s roster page, meaning we’ll be going in alphabetical order through each position group, starting with the pitchers. Today, we’re highlighting Luis Ysla.

The Question: Can Luis Ysla avoid the fate of Williams Jerez and take the next step?

Every winter, teams with room on their 40-man rosters fill those most of those open spaces with the minor leaguers they don’t want to expose to the Rule 5 draft. Sometimes, those players are top prospects like Blake Swihart, but most of the time they are closer to fringe players. This year, the last protection likely came down to Luis Ysla and Justin Haley. The former was protected and the latter was selected by the Angels and traded to the Twins. Since he was protected, one would imagine the Red Sox have plans for Ysla that could begin as soon as this year. Although that may be the case, it’s no guarantee. Some of you may recall what’s happened with Williams Jerez over the last year.

Jerez was in Ysla’s position in the winter of 2015. The converted outfielder was making an impression as a left-handed reliever, and the team protected him from the draft despite not having experience above Double-A. He didn’t quite take that next step in 2016, still failing to find his command in the upper levels. He survived the chopping block for most of the season, and remained on the 40-man until the team signed Mitch Moreland in December. At that point, Jerez was designated for assignment and cleared waivers. He remains with the organization.

The first part of that story is similar to Ysla’s, except instead of converting from the outfield Ysla simply converted from a rotation role. The lefty was acquired from the Giants in 2015 in exchange for Alejandro De Aza and was promptly shifted into the bullpen. In that role, he’s shown good stuff that should be able to play in the majors. However, like Jerez, Ysla hasn’t pitched above Double-A. In fact, both lefties failed to even pitch all that well with Portland.

That’s not to say there’s no appeal to Ysla’s game, though. Looking at the scouting reports, this is where he begins to separate himself from Jerez. Ysla’s main offering is his fastball, which will sit in the low-to-mid 90’s and shows off movement at its best. Sox Prospects gives it the potential for a plus-plus offering. For secondaries, he has a refined slider and a solid changeup. The breaking ball can be used against both righties and lefties and could turn into an above-average pitch. Jerez has the same offerings, but is at least a grade below Ysla for each one.

Despite the strong potential for each of his pitches, he hasn’t been able to utilize them as well as he can at the upper levels. His biggest problem last season — in which he made all but one appearance at Double-A Portland — was his command. Ysla wasn’t able to find the plate, and when he was he caught too much of it. Although he was able to strike out nearly ten batters per nine innings, he walked more than four. On top of that, his ground ball rate was just 38 percent and he allowed a .752 OPS.

Beyond the command profile, Ysla hasn’t really been a dominant force against lefties, either. In fact, he was demonstrably worse against them in 2016. To wit, he allowed a .947 OPS against them versus a .622 mark against righties. A large part of that was because of batting average on balls in play — he allowed a .451 BABIP to lefties in just 94 plate appearances — but it wasn’t all luck. The hard contact he allowed was made evident by the fact that he allowed three of his four home runs to lefty despite making up just 38 percent of his plate appearances. Even in 2015, he allowed OPS’s over .800 against both righties and lefties.

Right now, Ysla appears to be all projection. The tools are clearly there, and if he makes good on them he’ll be up in the majors at some point. This season will likely start at Triple-A, although it’s always possible they’ll send him on the Jerez route and have him repeat Double-A. If that’s the case, one would hope he can make a strong first impression and make his way up to Pawtucket before too long.

Left-handed reliever is an area of weakness on Boston’s roster, and Ysla may have the best potential of anyone involved in the competition. If all goes according to plan, he could very well be a mainstay on the major-league roster by the end of the year. The 25-year-old has a long way to go, though. If Ysla can’t figure out how to harness his stuff and improve his command, he could be off the 40-man roster by the time next spring rolls around.