The Jays have a solid system and a great collection of hitters but I am worried about the general lack of development/advancement of a lot of the arms outside the Top 10 list.
1. Vladimir Guerrero Jr. | 3B | AAA —> You’ve probably already read a lot about Guerrero Jr… so I’ll keep this fairly short. He has the chance to hit for average, power, get on base at a crazy-high rate and be one of the top hitters in all of baseball. He has limited defensive value but his instincts allow him to play third base for now. I do worry about his conditioning as he matures and, if he doesn’t make some changes now, may start to decline in his early 30s.
2. Bo Bichette | SS | AA —> Bichette receives his fair share of attention but perhaps not as much as he would if he were not sharing the limelight with Guerrero Jr. The young shortstop has swiftly risen through the system and reached double-A in 2018 at the age of 20 — a significant accomplishment. He also more than held his own in a league with an average age around 24. His quick bat generates plenty of raw power but he has yet to become a prolific home run hitter; instead, he slugged 43 doubles (with seven triples and 11 homers) in 131 games. Bichette is an aggressive hitter so there will likely be adjustment periods at both the triple-A and MLB levels as more experienced pitchers exploit those tendencies. He has 20-20 potential.
3. Danny Jansen | C | AAA —> Jansen’s rise from fairly obscure 16th round pick (2013) to big leaguer ended towards the end of 2018 and, although he looked tired at times, he fit right in and showed why he’s one of the best young catching prospects in the game. He has a good approach at the plate, he has some pop in his bat and a great eye. He should be an above-average big league hitter (for a catcher) in his prime years with excellent on-base numbers. Jansen is no slouch behind the plate and grades out as a future average (if not slightly better) contributor on defence. He should be the Jays everyday catcher in 2019 but the presence of Russell Martin complicates things, especially with another young catcher, Reese McGuire, also MLB ready.
4. Sean Reid-Foley | RHP | AAA —> I’ve been fairly critical of Reid-Foley in the past for perhaps some stubbornness when it came to accepting coaching recommendations and for having a less-than-ideal mound presence. Things seemed to click for him in 2018 and he made significant strides and became more of a pitcher and less of a thrower, while also becoming a little more mentally tough by not letting bad innings or poor calls get to him. I see a future innings-eating, mid-rotation arm. He has a fastball that can reach the mid-90s and three other offerings with average-or-better potential. If his fastball command continues to improve, he has a slight chance to be even better.
5. Eric Pardinho | RHP | R —> I’m probably in the minority by placing both Reid-Foley and Pardinho ahead of Pearson but I’m comfortable with the decision. The young Brazilian hurler is just 17 years old (let that sink in) and he was perhaps the best pitcher in the advanced-rookie ball league in 2018. He was homer prone at times, and may continue to be throughout his career, but he has excellent stuff, a great delivery, above-average command/control and excellent poise for his age. Just 5-10 (maybe), he can hit 95-96 mph and could eventually boast three plus offerings. The Jays may be cautious with him in 2019, after he threw just 50 innings last year, but I think he maybe moves up to full-season ball in May or June after a little time in extended spring training.
6. Nate Pearson | RHP | A+ —> Pearson is a great prospect but he’s also proven to be quite injury prone — and the screws in his elbow continue to concern me. Given how hard he throws (reportedly up to 103-104 mph with his fastball and 95 with his slider in the fall), Tommy John surgery may be inevitable. He has the raw stuff to be an un-hittable beast but I don’t know if his body can hold up to that kind of strain as a starter. Plus his control was below average in the Arizona Fall League. So, because of those concerns, Pearson is a future high-leverage reliever for me, with 12-18 months of lost development time potentially looming off in the horizon, which could potentially chew up some of his peak, inexpensive seasons. If I were running the Jays, I’d sell off while his value is at its highest (which may not be until he pitches a good stretch of innings in 2019).
7. Jordan Groshans | SS | R —> The Jays like to target players with strong offensive skills and good makeup/maturity and Groshans checks both of those boxes. He had an outstanding debut as a teenager and showed an advanced-approach at the plate for his age. Groshans has the makings of a player capable of hitting for average and producing 20+ homers. Defensively, he’s been playing shortstop and may be able to stick there but he might eventually shift to second or third base. He’ll likely move up to full season ball to open up the 2019 season.
8. Kevin Smith | SS/3B | A+ —> I’m not as big of a Kevin Smith fan as some. He had a great start to 2018 in low-A ball after making some adjustments in the winter but he regressed back to old tendencies in high-A ball, which was the more appropriate level for his age and experience. Now, he still hit more than .300 and was a 20-20 player so it’s not all doom and gloom but I need to see a better approach at the plate and more patience (BB-K of 40-121) before I’ll start to envision an above-average regular, especially if he moves to third base. I could see him ending up, offensively, in the Brandon Crawford to Scooter Gennett range depending on the adjustments he continues to make next year.
9. Hector Perez | RHP | AA —> Perez has special velocity with the ability to work in the mid-to-upper 90s. He also has two breaking balls that flash plus potential. Unfortunately, the right-hander currently has both below-average command and control. When he’s pitching well, Perez will induce a ton a ground balls to go with strong strikeout rates. He did an excellent job of keeping the ball in the yard and allowed just six homers in 115 innings, which is a great skill to have in the AL East. If he cannot throw enough strikes to pitch as a starter, he’ll make an excellent high-leverage reliever. Perez will likely spend most of 2019 in double-A.
10. Cavan Biggio | 2B | AA —> I’m not 100% sure what to make of Biggio but I don’t really see an everyday player here. He’s got big league potential but it’s probably as more of a platoon or part-time guy that gets into a game 4-5 times a week. The Jays have already had him playing second base, third base, first base and the corner outfield. He has 20+ homer potential but his swing gets long and he Ks a lot. On the plus side, he offsets that with a ton of walks and produced a BB-K of 100-148. I don’t see him hitting for average with his current approach but the walks will help him produce a solid on-base rate.
Miguel Hiraldo | 3B | R —> Considered one of the top hitters on the international market in 2017, Hiraldo has shown flashes of being a good hitter but he’s not quite as polished as expected. He opened the year in the Dominican Summer League despite the fact most top international signees jump right to North America. He swings and misses too much but definitely showed his raw power potential with a ton of doubles that should eventually turn into over-the-fence pop. He doesn’t have a ton of defensive value but reportedly has good makeup so he could turn into an average third baseman.
Adam Kloffenstein | RHP | R —> Kloffenstein threw just 2 innings after turning pro due to a heavy prep workload but he has all the makings of a mid-rotation, innings-eater… if not more. His velocity is inconsistent right now but the right-hander has shown the ability to work in the mid-90s and both his breaking ball and changeup have shown flashes of being better-than-average. Expect him to open 2019 in extended spring training while working on throwing strikes more consistently.
Rowdy Tellez | 1B | AAA —> Tellez’s star was burning bright in 2016 but he went through some personal struggles over the past two years while playing at the triple-A level. He showed signs of life with the bat in the second half of 2018 and earned a late-season promotion to the Majors where hit exceptionally well — slugging 13 extra base hits in 23 games. Tellez has a shot at breaking camp with the Jays in 2019 if the club can find a taker for either Kendrys Morales or Justin Smoak (the more valuable of the two). Tellez should hit for solid pop — but has never been a huge power guy — but it remains to be seen how well he’ll hit for average. He’s limited the Ks in the minors but doesn’t walk a ton and he had a 2-21 BB-K rate in his debut.
Marc Hulet has been writing at FanGraphs since 2008. His work focuses on prospects and fantasy. Follow him on Twitter @marchulet.