20. Antonio Santos (154 points, 15 ballots)
Antonio Santos represents a late bloomer for the Latin America program. The 23-year-old right-handed Dominican starter was only signed when he was 18 (in 2015), for a $50,000 bonus. Over the last five seasons, he’s slowly worked his way up the minor league ladder to AA and a stint in the AFL this past fall, ultimately leading to a coveted 40-man roster spot.
After dominating the DSL in his pro debut, Santos distinguished himself as one of the youngest starters in the league in the Short Season A Northwest League in 2016, the Low A South Atlantic League in 2017, the High A California League in 2018 (via a mid-season promotion), and the Double A Eastern League in 2019 (another mid-season promotion). In making this progress, Santos distinguished himself with his ability to soak up innings (he’s thrown over 140 each year the last three years) with good K/BB numbers against older hitters.
In 2019, Santos began the year as a repeater in High A Lancaster against hitters that were on average about 1.2 years older in one of the most intimidating environments for pitchers in all of minor league baseball. On this canvas, the 4.35 ERA, 3.74 xFIP, 1.35 WHIP, 8.7 K/9 rate, and 1.6 BB/9 rate Santos put up in 99 1⁄3 innings over 18 starts is a strong performance.
The Rockies agreed, moving him up to AA Hartford in late July. With Hartford in a more neutral environment but against hitters that were on average about 2.3 years older, Santos fared well. In eight starts with Hartford, Santos threw 45 2⁄3 frames of 4.93 ERA, 3.21 xFIP, 1.25 WHIP, 8.7 K/9, 2.0 BB/9 ball. That performance was enough to get Santos on the Arizona Fall League roster, where he appeared as a reliever in eight games, throwing 13 innings with a 16:2 K/BB ratio and 2.77 ERA against fellow top prospects. The showing secured Santos as a prospect worth the 40-man roster slot the Rockies gave him in November.
Here’s some video of Santos from the AFL courtesy of 2080 Baseball, where his fastball sat in the mid-90s:
Accompanying the above video is this report from 2080 Baseball’s Adam McInturff, complete with granular arsenal and mechanics grades (overall a 45 FV grade as a set-up reliever). The whole thing is worth reading, but this is the summary:
Big stuff without pitchability/consistency to fully harness it in SP role; strikethrowing over 3-4 power pitches and ability to pitch multi-inning stints give high-end 7th inning or decent setup RP upside; like him in the ‘pen and could come quickly there.
Santos is ranked 19th in the system by Jeffrey Paternostro of Baseball Prospectus:
Santos is an interesting arm strength flyer. He can run his fastball up into the upper 90s—and sit mid-90s in short bursts—but the pitch tends to run a little true, and a violent finish to his delivery suggests the command profile may not be fine enough to start. He does have a little hitch/hesitation which can create timing issues for the hitters, and he’s effectively wild with the heater.
Santos has a full four-pitch mix, but both breaking balls are below-average—a slurvy curveball will occasionally flash decent tilt—and the changeup is inconsistent. The change will at least flash some hard fade and dive, but it’s firm, and fastball/changeup relievers are a rare bird. There’s some swing/spot start potential here and maybe you can get one of the breakers to average to give him a shot at middle relief, but it’s a tough major league profile even before you consider his future home park.
The FanGraphs evaluation gives him a 40 FV, ranking him 22nd in the org:
Santos’ fastball velocity range is rather vast, but when he was coming out of the bullpen during Fall League, he was sitting 94-97 for entire outings. He doesn’t have a bat-missing secondary; rather he has a deep well of average pitches from which to draw. Whether he’s a No. 5/6 starter type or his repertoire gets pared down to what Colorado thinks gives him the best chance of missing bats out of the bullpen, we think Santos is clearly a rosterable arm of some kind.
Santos will probably start 2020 in AA again with a mid-season promotion to AAA assuming all goes well. That written, there’s a chance that he’ll factor into the big league roster one way or another this year given his 40-man roster slot and utility in both the ‘pen or the rotation.
It’s not hard to squint and see a MLB outcome for Santos that mirrors that of past Rockies Latin America starter prospects with blah secondary pitches like Juan Nicasio and Antonio Senzatela: a back-end starter better suited to middle relief or set-up work at the big league level. Then again, every prospect is a different animal and I don’t want to put Santos in that box just yet, as he’s still very much an interesting starter. The starter potential and relief fall-back role led me to rank Santos 22nd on my personal list with a 40 FV grade.