Prospect Stock Watch: Mining the 2018 Draft for Hidden Gems

The 2019 MLB amateur draft is just over a week away! The Prospect Stock Watch has been devoting time to reviewing the 2018 draft. Earlier this week, we reviewed the second round of the draft. Today’s piece is going to look into which players have so far represented the best value from the third, fourth and fifth rounds.

This piece will naturally favor college picks as they’re generally more advanced and many of the prep players taken in later rounds of the draft require extra time in extended spring training before joining full-season ball. This piece looks at players’ results as well as the potential ceilings they possess based on their tools.

Best third-round pick: Terrin Vavra, SS, Rockies

When the year began, I would have hedged my bets towards Tristan Pompey or Kody Clemens being the steals of the fourth rounds. But Pompey posted a strikeout rate near 50% in High-A ball and earned a trip back to extended spring training to work things out. Clemens is still in High-A but he’s struggled to hit consistently and his 25% strikeout rate is high for someone who’s not a power hitter. That leads us to Vavra, who was drafted out of the University of Minnesota, and with less pedigree – although his brothers played pro ball, too. The middle infielder has shown good pop and a solid plate approach with a BB-K of 21-36 in 41 games. The line-drive rate sits at 24% and once Vavra gets a little stronger, he should start to hit even more balls over the fence. It remains to be seen if Vavra can stick at shortstop but he appears to have the offensive profile to stick at a number of different positions.

Runner Up: Owen Miller, SS, Padres

San Diego though enough of Miller’s strong pro debut in 2018 to jump him over High-A ball and assign him directly to Double-A. He’s barely missed a beat with a .301 average, and has now hit .300 at every level he’s played out. The downside to Miller is that his ceiling is somewhat limited with modest power and limited stolen base acumen. With that said, and although just 13 of his 52 hits have gone for extra bases, he has generated a 27% line-drive rate so there could be more gap pop (ie. doubles and triples) to come as he matures. He’s even more likely to end up at second base, or serve as an offensive-minded utility player.

Best fourth-round pick: Kyle Bradish, RHP, Angels

Bradish is hardly a well-known name even among prospect circles but the pitching-starved Angels have to be thrilled with what they have in the right-hander. With a great pitcher’s frame, he should be capable of chewing up lots of innings as he matures, if he can stay healthy. Bradish has a slightly-above-average fastball, as well as an above-average curveball which has helped him strike out 48 batters in 38.1 High-A ball innings. He also induces above-average ground-ball rates, which has helped him survive the potent California League — and in fact, he’s given up just one home run. If he continues this development path, Bradish looks like a potential No. 4 starter.

Runner Up: Frank German, RHP, Yankees

The Brewers Aaron Ashby has better numbers but he’s been doing it at Low-A rather than High-A where German has produced solid results. The Yankees’ prospect has battled his command and control but he has a low-to-mid-90s fastball that overpowers hitters when it’s on. He’s still working on his secondary offerings — including a reliable breaking ball — but if something clicks, he could be a solid back-end starter. If not, he could end up as a valuable seventh- or eighth-inning reliever.

Best fifth-round pick: Ryley Gilliam, RHP, Mets

Gilliam doesn’t have as high of a ceiling as the runner-up but he’s already pitching at Double-A after opening the year in High-A ball. He’s undersized and listed at 5-foot-10 but he can still dial the heater up to the mid-90s and possesses a promising breaking ball that he can use as an out-pitch. So far this year, batters are hitting just .192 against him with 34 strikeouts in 20.2 innings. His lack of height doesn’t allow him to get great plane on the ball and he allows a lot of fly balls but he’s only given up one home run as a pro (38 innings) and none this season.

Runner Up: Chris Vallimont, RHP, Marlins:

As well all know, teams cycle through many, many arms in any given year so depth is incredibly important and the ability to find arms deeper in a draft is always key to any team’s success in building a reliable farm system. And the Marlins don’t have a great system so Vallimont could be a real find. He played at a smaller college where he produced excellent strikeout numbers. That swing-and-miss success has continued into his pro career and he currently has 61 strikeouts over 53.1 innings in Low-A ball. There are a couple of other former college pitchers that are doing well in Low-A but they also played against better competition on a regular basis as amateurs and should be further along in their development. Vallimont is still just scratching the surface of his potential and stands 6-5 but still looks skinny at 220 pounds. He can get into the mid-90s with his heater and backs it up with a very good excellent breaking ball. His delivery is easy and loosen; there could be more velocity to come as he fills out.