Champ or Chump: Josh Rojas and Aristides Aquino

While the top prospects likely to debut in 2019 have largely dried up, players coming up from the minors are probably still the best way to add a new dimension to your roster. The Arizona Diamondbacks have summoned Josh Rojas from the minors to play a utility role, and he has a chance to be a godsend for owners looking for steals.

If you haven't heard of Aristides Aquino, you've probably been under a rock for the last week and a half. The 25-year old rookie's big league career is off to a scintillating start, but both his peripherals and MiLB history suggest that he's more of a Mike Jacobs than an Albert Pujols.

Keep in mind, our Champ / Chump conclusions are based on whether we think a player will outperform their expectations. For example, a pitcher we view as "Tier 2" can be a Champ if they're seen as a Tier 3 pitcher, or they could be a Chump if they're perceived as a Tier 1 pitcher. All ownership rates are from Yahoo! leagues unless otherwise noted. Let's take a closer look at Rojas and Aquino, shall we?

Josh Rojas (2B/SS, ARI)

22% Owned

The 25-year old Rojas has two big league games under his belt as of this writing, and playing for Arizona isn't exactly the best way to get noticed in fantasy circles. Still, his MiLB profile suggests a blend of plate discipline and speed that could give him tremendous upside in the fantasy game.

Rojas reached the High Minors in 2018, slashing .251/.338/.385 with seven homers and 26 steals (14 CS) over 451 PAs for the Double-A affiliate of the Houston Astros. While you'd like to see something better than a 65% success rate, fantasy owners are always interested in guys with 30 SB potential. He also drew a lot of walks for somebody obviously looking to run (11.8 BB%), and generally avoided strikeouts to boot (16.9 K%). A 5.6% HR/FB isn't great for his power potential, but it was an intriguing debut for fantasy purposes.

It wasn't quite as valuable in real baseball terms, so the Astros asked Rojas to repeat the level this season. He fared much better, slashing .322/.405/.561 with eight homers and 13 steals (six CS) over 195 PAs. He continued to walk (11.3 BB%), avoid Ks (14.4 K%), and get caught stealing too often (68% success rate), so it was largely more of the same. A BABIP spike to .348 improved his average, while a HR/FB spike to 15.7% added some pop to the package.

The performance earned Rojas a chance at Triple-A, where he slashed .310/.402/.586 with 12 HR and 19 SB (four CS) in 244 PAs as Astros property. He walked (12.3 BB%), didn't strikeout (14.8 K%), and dramatically improved his stolen base success rate (83%), so the more advanced competition didn't bother him in the slightest. He also ran a .325 BABIP and a 17.6% HR/FB.

The Diamondbacks were apparently more impressed than the Astros with his work, leading to his inclusion in the Zack Greinke deal. He slashed an insane .514/.575/.943 with three homers and a steal in 40 PAs at Triple-A for them before earning a promotion to the big club.

Baseball Savant sees league-average hit and power from Rojas, with 45-grade foot speed that plays up thanks to his aggressive approach on the bases. He doesn't have any prospect pedigree (26th-rounder in 2017) and has been fairly old at his MiLB stops, but it's hard to pass on a jackrabbit with plus plate discipline in fantasy. He also has professional experience in the outfield and all four infield positions, making him easy to plug in when one of your regulars gets a day off. While it remains to be seen how often Arizona will play him, Rojas is a worthwhile roll of the dice if you have a need for speed.

Verdict: Champ (based on positional versatility, SBs, and plate discipline in the minors)

Aristides Aquino (OF, CIN)

75% Owned

Aquino has slugged eight homers with a .385 average in 42 PAs at the big league level this season, but he does not seem like a good bet to keep up anywhere near that level of production. He first reached Double-A in 2017 and looked completely overwhelmed, slashing .216/.282/.397 with 17 long balls and nine steals (three CS) in 504 PAs. He struck out too often (28.8 K%) and didn't walk nearly enough to make up for it (7.7 BB%).

Worse, Aquino was the master of popping out. He elevated the ball well (45.3 FB%), but a ludicrous 34 IFFB% dragged his BABIP down to .274. IFFB% is calculated differently on the farm, so you need to halve MiLB rates to get an MLB equivalent. Still, a high fly ball rate and 17 IFFB% would make it virtually impossible for Aquino to hit .230 over a full season in the major leagues. It might have been acceptable with a higher HR/FB, but Aquino's rate of 12.1% simply doesn't cut it.

Aquino repeated Double-A in 2018 and had almost the same terrible season, slashing .240/.306/.448 with 20 HR and four steals (five CS) in 445 PAs. His K% improved to 25.2, but he still didn't walk (7.9 BB%) and popped up way too often (42 FB%, 35.5 IFFB%). The resulting BABIP of .282 and 16.5% HR/FB were slight improvements, but Aquino looked like minor league roster filler at best.

The Reds promoted him to Triple-A to begin this season (no idea why), and his production spiked to .299/.356/.636 with 28 HR and five steals (one CS) over 323 PAs. His BABIP jumped to .321, but he was still the same fly ball guy (43.3 FB%) with way too many pop-ups (33.3 IFFB%). His plate discipline metrics (25.1 K%, 7.1 BB%) were also virtually unchanged from his prior campaign. The biggest difference between the two seasons was a 30.1% HR/FB, something that's at least as likely to be the result of the new ball at Triple-A as anything Aquino did.

To be fair, Aquino dramatically changed his batting stance in 2019. It may have played a role in him accessing his power (65 Raw Power but 55/60 Game Power per FanGraphs), but his IFFB% was just as bad on the farm this year as it had been in the past. Worse, his MLB plate discipline indicators (43.3% chase rate, 18.5 SwStr%) suggest that he would be lucky to maintain his current 28.6 K% in the Show. Even with the change in approach, there appear to be a lot of holes in Aquino's game.

Aquino's contact quality metrics also have some red flags in his small MLB sample. His 95.4 mph average airborne exit velocity is good, but you would think it had to be great considering what he's done so far. His 75.6 mph average exit velocity on grounders is also well below average. His 25.9% rate of Brls/BBE is great, but it's way too small a sample to call that his true talent level. He has a 7.7 IFFB% thus far, but his minor league track record suggests that it'll skyrocket once his hot streak ends.

In short, Aquino brings a combination of pop-ups and strikeouts to the table that virtually disqualify him from major league success. You can ride him while he's hot (especially since the Reds are batting him cleanup), but the smartest move is probably to trade him while you can. He would need to completely reinvent himself to be a viable long-term big leaguer.

Verdict: Chump (based on weak MiLB performance and troubling strikeout and pop-up trends)

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