Oakland A’s prospect watch: Logan Shore and Skye Bolt thriving in High-A repeats

The High-A Stockton Ports are 18-13, tying them for the best record in the eight-team California League. Most of that success has come at the hands of some new 2018 additions, but lately a couple of familiar faces have returned and given the club a boost.

First up is pitcher Logan Shore, who ranked No. 13 on our preseason Community Prospect List. Shore missed a big chunk of 2017 to a lat injury, then struggled upon his return later that summer. Overall he posted strong peripheral stats in High-A, but his results were only mediocre and he then got smashed in the Arizona Fall League. He was expected to move up to Double-A this year, but another lat flareup in the spring delayed the start of his season.

Now Shore is back in game action, albeit in a repeat at High-A. He threw four efficient innings in his debut outing, and then followed that up with six scoreless frames on Saturday.

Shore, 2018 A+: 0.90 ERA, 10 ip, 14 Ks, 1 BB, 0 HR, 6 hits, 1.98 FIP

It’s only two games, but hopefully this is a sign that he’s healthy and ready to continue his development. The next question is what exactly the A’s will be looking for before moving him up to Double-A, but if I were to guess (pure speculation) I’d say it’ll happen sooner than later considering he was originally headed for Midland in the first place. There’s certainly nothing blocking him from the RockHounds rotation, which currently features more org filler than actual prospects.

The other Stockton standout is outfielder Skye Bolt, who barely cracked our Community Prospect List at No. 26. He also dealt with some injuries in a mediocre 2017 in High-A, but unlike Shore he was healthy to start this year and punched his ticket up to Double-A. Unfortunately, once there his bat utterly disappeared: 6-for-45, a .133 average, 13 wRC+, and strikeouts in a third of his plate appearances. It only took 11 games for him to wash out back down to Stockton.

This time around, the 24-year-old is blasting the Cal League. He’s still got some swing-and-miss and the high strikeout rate to match, and he’s benefiting from a higher BABIP than normal. On the bright side, though, he’s drawing a ton of walks and hitting for serious power. Considering half his hits have been for extra bases, it’s at least possible he’s earned some of that extra BABIP.

Bolt, 2018 A+: .311/.415/.644, 176 wRC+, 3 HR, 13.2% BB, 28.3% Ks

It will take a bit more time to determine how much of his breakout is real, but this first impression is probably the most encouraging thing he’s done so far in his pro career. He’s always been a toolsy athlete looking to translate raw talent into production, and perhaps he’s finally doing that. We’ll see if he keeps it up, both in Stockton and then when he presumably finds his way back up for another try at Double-A.

Rotation settles in

Stockton’s rotation got off to a scorching start, and their ace Jesus Luzardo moved up to Midland almost immediately. Now that the sample size has grown, the rest of the group has cooled off a bit. (Note: Dunshee has made one more start than the rest.)

The top performers are still Parker Dunshee and Brian Howard, who both made the bottom of our CPL. Dunshee has finally given up a few runs (after last year’s 0.00 ERA), but his swinging-strike rate (15.1%) is among the highest for all Cal League starters. Howard has finally issued a few walks (after last year’s 29.0 K/BB), but his minuscule 8.6% line-drive rate suggests he’s inducing his opponents into poor contact. They’re still the names to watch here.

As for the others:

• Zack Erwin has alternated between excellent and disastrous in his games. Most of all, as a soft-tosser he really needs to cut down that walk rate, since I’m not expecting him to keep striking out a batter per inning all the way up to MLB.
• I have no idea what to make of Jake Bray. As a reliever he was a strikeout monster who was only mediocre at preventing runs, and now as a starter he’s not striking out anybody but nobody can score off of him. One thing I can say for sure is that he’s not going deep into games as he stretches out in the rotation, but on the bright side each of his last two times out he did make it through five innings. Beyond that, we’ll just have to wait and see where he goes from here and which part of his unsustainable stat line changes.
• Finally, Matt Milburn is quickly dropping off any radar, at least as a starter. He still has the K/BB rate that’s kept him in the corner of my eye since he was drafted in 2016, but hitters are teeing off when they do make contact. He’s got plenty of time to turn it around, but if I had to guess I’d say he won’t be interesting again until/unless he moves to the bullpen.

Bullpen heating up

While the rotation has come back to Earth, the Ports’ pen has stepped up in its place. As if to drive home my point about Milburn, the leaders have been a couple of former starters who are now finding substantial success in shorter roles.

Angel Duno spent the last five years in Oakland’s system as primarily a starter, but now at age 24 he’s thriving in relief. He’s previously suffered from the same problem as Milburn — fantastic K/BB rates, but torched by batted balls. Now he’s keeping the good parts and shedding the bad parts, with a career-high strikeout rate and a drastic reduction in hits and homers. His swinging-strike rate is a personal best at 15.9% (up from 9.6, 9.9, and 13.8 the last three years), and he’s keeping the ball on the ground nearly half the time. Standard small-sample disclaimers apply, but this is the most encouraging step forward I’ve ever seen from Duno.

Meanwhile, Boomer Biegalski began his transition to the bullpen last summer in Stockton and pitched well in a dozen games: 31⅓ ip, 36 Ks, 8 BB, 3 HR. Now the 2015 draftee is outright dominating, striking out more than a third of his batters (38.5%) and earning whiffs on a fifth of his pitches (19.7%). Both of those marks lead the Ports, at least now that Luzardo is gone.

Finally, Miguel Romero is quickly coming into his own in his second year of U.S. ball. Walks were never a problem before but now are completely nonexistent, and whereas opponents blasted him last year they now can’t buy a hit — only seven of them in 16 frames, out of 54 batters faced. This one will take more time to believe since it’s based on hits rather than FIP components, but Romero has long been praised for his raw stuff and for now it’s finally translating into eye-popping stats.

Two lefties also warrant a quick mention. Andrew Tomasovich has given up a few runs but is building some impressive peripheral stats (14⅓ ip, 20 Ks, albeit 11 BB), and Will Gilbert hasn’t yet allowed a hit in six innings (his 18.6% swinging-strike rate trails only Biegalski on the team). Considering the complete lack of lefty depth in the system, these 24-year-olds qualify as two of the most interesting southpaw relief prospects.

Lineup, briefly

There’s not much to say about the lineup, outside of Bolt. A couple of the top names are on the DL, and the other high-profile prospect is struggling: Kevin Merrell is down to a 77 wRC+ thanks to no walks or power, and he’s not yet getting on base enough to flash his elite speed.

The best remaining bat belongs to catcher Jonah Heim, who’s hitting for a good average, controlling the zone well, and adding a little power too. Like with the lefty relievers, there is virtually no catching depth in the system outside of Sean Murphy, and that makes the 23-year-old switch-hitting Heim slightly more interesting than he might otherwise be.

Heim: .311/.387/.434, 123 wRC+, 2 HR, 10.1% BB, 18.5% Ks

Honorable mention to infielder Edwin Diaz, who leads the Ports with five homers. Dishonorable mention to converted outfielder Eric Marinez, who caught an 80-game suspension for a PED violation (reports Melissa Lockard, Oakland Clubhouse).

Tuesday’s games

Full slate of action.

Triple-A Nashville: 4:35 p.m., James Naile vs. Colorado Springs
Double-A Midland: Lost 3-0, Norge Ruiz vs. Frisco
High-A Stockton: 6:00 p.m., Brian Howard vs. Visalia
Single-A Beloit: 4:30 p.m., Xavier Altamirano vs. Great Lakes

Naile faces the lineup that hammered him at altitude last time out, but this time it’ll be in the pitcher-friendly confines of home. Midland got shut out but did so without their two best hitters (Ramirez and Murphy got the day off), and Ruiz spun a quality start despite the loss.

And of course, even though this post was about High-A Stockton, we’ve got to mention the full-season debut of Lazaro Armenteros yesterday. The teenage outfielder suited up for Single-A Beloit and went 1-for-5 with a double, a sac fly, and three strikeouts. More on him in our next Beloit update.

Link to box scores