Pittsburgh Pirates Prospects: Sleeper Player From Each Minor League Level

Bradenton - RHP Ryan Harbin

Bradenton has a handful of pitching prospects who you could file as a sleeper prospect. However, the most talented among the Low-A relievers and the one with the best chance of making a significant impact in the Major Leagues in the near future is Ryan Harbin. A former 17th-round pick in 2019, Harbin is still only 21 years old. This year, he’s tossed 26 innings, allowing just three earned runs, which is good for an ERA of just 1.04. He also holds an strong 3.04 FIP and 1.08 WHIP.

On top of that, he has elite peripherals. Harbin has struck out 33.6% of his opponents while working a manageable 10.3% walk rate. However, his ability to limit the long ball is his biggest strength, and he is one of the best home run limiters in the system. Harbin has allowed just a single home run all year, but what’s even more impressive is his ability to keep the ball on the ground. We call Quinn Priester a ground ball machine, and he typically has a ground ball rate around 50-60%, but Harbin clocks in with a ground ball rate at 70.7%.

Harbin’s primary pitcher is a sinker that he throws in the mid-upper-90s. He consistently sits around 95-96 MPH with the pitch. He throws both a cutter and a slider. Although Harbin’s sinker only sits with around 2000-2200 RPM, his slider and cutter approach 3000 RPM. His cutter/slider averaged out at 2847 RPM in his most recent outing and topped out at 2989.

The Pirates could move him through the system with more authority because Harbin is a relief pitcher. The right-hander could potentially be the organization's next top relief prospect. There’s a good chance that Harbin will make his debut late into 2024. He’ll likely at least make it to one of the upper levels of the minor leagues next season, if not start the year at Altoona or Indy.

Greensboro - LHP Cy Nielson

Now moving up to Greensboro, we’ll turn out attention to another relief pitching prospect. This time, it’s left-hander Cy Nielson. The Pirates selected Nielson in the 8th round of the 2022 draft. Only 22 years old, Nielson has already carved out a high-leverage role with Greensboro and could very well get moved to the next level of the minor leagues very shortly.

Nielson has been nothing short of outstanding for Greensboro. In 26 innings, the Southpaw owns a 2.42 ERA, 2.92 FIP, and 1.08 WHIP. Nielson has a strikeout rate of 30.3% but is also rocking a strong 8.3% walk rate. However, like Harbin, Nielson’s ability to limit home runs is unmatched. He’s arguably the best at limiting home runs in the minor leagues right now for the Pirates. Nielson hasn’t generated ground balls at the same rate that Harbin has, but he still has an elite 62.1% rate. That’s undoubtedly helped him in allowing zero home runs all year.

Not allowing a single home run in an extended look at Greensboro is very impressive. He’s taken over a late-inning/high-leverage role for Greensboro as well, racking up four holds and seven saves. While Nielson has been a highly effective late-inning arm so far this year, he doesn’t have the same stuff you’d typically see from relievers.

Nielson sits in the low-90s, topping out around 95 MPH. However, he throws a sweeping slider that averaged out over 40 inches of vertical break last season. Nielson also throws a low-spin change-up. He’s not a high-octane reliever, and while there is a chance he can add an extra tick of velocity, he’s shown he can be highly effective despite the lack of speed.

Altoona - RHP Sean Sullivan

I’ve said it before, and I’ll say it again, Sean Sullivan is my favorite unranked pitching prospect in the Pirates’ system. An 8th-round pick in 2021, Sullivan’s 2022 season had its pros and cons, but it certainly led to a decent amount of promise going forward. Now at Altoona, Sullivan has continued to be a solid pitcher.

In 47 innings, Sullivan owns a 2.87 ERA, 3.77 FIP, and 1.17 WHIP. While Sullivan’s strikeout rate is 21.1%, he holds a robust 7.8% walk rate. On average, Sullivan allowed nearly two home runs every nine innings in 2022. But he’s cut his HR/9 to just 0.77 this season. Weirdly enough, despite cutting his HR/9 down by over a whole home run, he’s become much more of a fly ball pitcher.

Sullivan only sits in the low-90s but can hit 94-95 MPH. When Sullivan throws his fastball low in the zone, it has some sinking action, but it can ride through the top of the zone when he throws high. He pairs that with a low-80s slider and upper-70s curveball. Of his two secondary offerings, his slider is the better one. He also throws an upper-80s changeup with some fading action.

Sullivan also has a surprising amount of deception in his wind-up. The way he winds up almost makes you think he’s a sidearmer. But then he releases the ball at a three-quarters arm slot. It’s also a swift arm motion, going from wind-up to release in a whippy, high-speed action.

Sullivan is deceptively young. He’s only 22-years-old and won’t turn 23 until October second. He’s the second youngest pitcher at Altoona, formerly flanked by Jared Jones and now by Anthony Solometo. But there’s a chance for four average offerings and above-average command within Sullivan.

Indianapolis - Utiltiy Aaron Shackelford

It’s easy to overlook anyone on Indianapolis’ roster, given how much talent they now have. Even guys like Malcom Nunez, Jared Triolo, and Colin Selby are now getting overlooked because of who is now at Triple-A. One player who has just been a role player throughout his minor league career is Aaron Shackelford, who’s posted respectable numbers at every level despite being considered a non-prospect by most.

An NAIA selection, the Pirates took Shackelford in the 14th round of the 2019 draft. Shackelford had a monstrous year in his final season at The Masters University, where he went deep 36 times in only 242 plate appearances. While he hasn’t been able to maintain Barry Bonds-esque production as a pro, he’s certainly been more than serviceable at every level.

This year, Shackelford is batting .246/.381/.455. Shackelford has been a surprising power/speed threat, swatting eight home runs and swiping six bags in seven attempts. Overall, he has a quality .210 isolated slugging percentage. Shackelford has always been a patient batter, drawing a ton of walks, and currently has a 16.1% walk rate, which would be a major uptick from the 8.7% rate he had in 2022. However, this has come at the cost of his strikeouts. His 28.8% strikeout rate is only a 0.6% upgrade from 2022.

Shackelford has moved all around the diamond as a pro player. He’s split most of his time at first base and second base but has a handful of games spent at the hot corner. He also played some right field last season. While he might not be renowned for his defense, he’s played a respectable glove at whatever position he’s been asked to play.

Shackelford is definitely the most underdog name we’ve discussed today. A 26-year-old who came from an NAIA school and was drafted in the 14th round doesn’t scream ‘top prospect.’ However, it would make for a great story if Shackelford were to become a productive major leaguer. He might not become the Pirates’ next superstar, but he has the potential to be a bench player who can provide some pop and utility. Personally, I’d certainly like to see him more than Mark Mathias.