Minor League Ball Ranking: 13th (Rangers)
Minor Leauge Ball Grade: C+
Luis Sardinas is now the Brewers best defense shortstop. It's by a wide margin too. While Jean Segura is probably at a similar level with his arm and his speed, his fielding is much closer to a 50 and might even be a 45.
At just 21 years old, none of Sardinas skills should depreciate while he is with the Brewers. They'll have team control over him through the 2020 season. In fact it's entirely possible, if not likely, he will improve during that time.
Having only played 60 games in AAA last year he might lack some polish. It's conceivable the Brewers feel he could benefit from further grooming at AAA. With Jean Segura and Hector Gomez currently on the 40-man roster they have that flexibility.
The one area where Sardinas vitally needs to improve is hitting. He has no real power of which to speak. Expecting 5 home runs in a season is probably hoping for too much. He also doesn't have much of a line drive swing which doesn't allow him to take advantage of his speed. He also doesn't draw walks.
Defensively we're going to learn to love Luis Sardinas. Offensively we're going to learn to really appreciate his defense. He was kind of holding his own in the lower minors hitting at or even above a 100 wRC+. However the second he hit AA in mid-2013 his offense fell off a cliff.
Without knowing what might have impacted him developmentally, I can immediately see that his BB% was more than halved. He went from 7-8% down to 2-3%.That's really bad, even for a speed slap hitter. With a 4.0 BB%, his triple slash during his time with the Rangers last year was 261/303/313. For right now that seems like his realistic talent level. If that's true, he's very like more of a utility player than a regular.
Basically, he's a singles machine. He's going to have a largely empty batting average. If he can't learn to draw walks to help boost his offense he'll need to hit for a high average if he wants to become a solid average regular (2-3 WAR) at shortstop. Even with his speed and defense.
Fortunately youth is on his side. The Brewers seem to be willing to give fringey players the time they need to grow into their skills. Khris Davis was viewed as a DH with a sketchy bat. Scooter Gennett was viewed as a utility player. Both Wily Peralta and Jimmy Nelson were thought, by some, to be better suited to relief work. Even Jean Segura was thought to be a better fit at second base. The Brewers gave all of these kids a chance to prove themselves. At this early stage I assume the same will hold true for Luis Sardinas.