Now that Darwinzon Hernandez has had his taste of the big leagues and is likely to return there this season, the obvious question is: who’s next to go from Portland to Fenway Park?

Tanner Houck had a rough start in his Double-A debut with the Sea Dogs on April 6, but since then he has allowed just one earned run in 10 innings. Brianna Soukup/Staff Photographer

After Hernandez, Boston’s highest-ranked pitching prospect is also with the Double-A Sea Dogs.

But Tanner Houck isn’t yet checking the Amtrak schedule out of Portland.

“That was really cool and it’s very easy to let your mind wander,” Houck said of Hernandez’s promotion. “But I just show up on the field and honestly, take it moment by moment. After I get one thing done, I do the next, then the next …”

Good or bad, Houck moves on. So after his Sea Dogs debut featured his worst professional start, Houck picked himself up — “learn from it and come back strong,” he said following the game — after allowing 11 hits and seven runs in four innings against Reading on April 6.

In his next three starts, Houck has totaled 10 hits and one earned run in 16 innings, including six shutout innings Saturday at Binghamton for his third straight win.

Houck, 22, was Boston’s first-round draft pick (24th overall) in 2017, receiving a $2.6 million signing bonus. He was the team’s highest-drafted college pitcher since Matt Barnes (19th overall) in 2011.

Barnes is now one of Boston’s top relievers. Hernandez, a Sea Dogs starter, is likely to be used in relief in Boston, as in his debut Tuesday.

As for Houck, his fastball-slider combination makes for a tempting assignment in the bullpen. But hold that thought.

“I’m not going to say he’s a reliever,” Sea Dogs pitching coach Paul Abbott said. “There’s not that many 6-foot-5 power-throwing, sinkerball right-handers. He just needs to get some wrinkles ironed out.

“If he gets those ironed out, we might have something special.”

Heading into Saturday’s start, Houck had a career record of 9-15 with a 4.23 ERA and 74 walks in 155 innings.

Special? Well, yes, if you look at the process.

Tanner Houck, Boston’s first-round draft pick in 2017, was promoted by the Red Sox to Double-A Portland at the start of this season. Brianna Soukup/Staff Photographer

Houck, a native of Collinsville, Illinois — “about 20 minutes from downtown St. Louis” — became the ace at the University of Missouri before the Red Sox drafted him. At short-season Lowell in 2017, Houck looked fine in 10 abbreviated starts (3.63 ERA, 25 strikeouts/eight walks in 22 innings).

In 2018, Boston decided to test its top pick and skipped Houck over Class A Greenville straight to advanced Class A Salem.

The move looked disastrous. On June 9, Houck was 2-6 with a 6.16 ERA, and 38 strikeouts/37 walks in 49 2/3 innings.

But that’s where the process comes in. Houck is primarily a two-seam/sinkerball pitcher. The Red Sox wanted him to show more variety and also use a four-seam fastball.

“A little bit of me trying to get away from myself. I was trying to be a four-seam guy that lived up in the zone and get that ‘rise action,’” he said. “The mechanics were kind of out of whack, which caused the arm action to variate, which caused for a lot of misfire.

“Nothing was the same and consistent, which is what everyone preaches. Consistency makes for a great ballplayer.”

Houck looked anything but great but kept working. He went back to primarily using the two-seam sinker but was now able to also bring high heat — with results. After June 9, Houck was 5-5 with a 2.86 ERA, and 73 strikeouts/23 walks in 69 innings.

“He’s got that ability to pitch on top of the zone, and he has so much run on his sinker,” Abbott said. Batters “have to defend against both. If he can command that four-seam on top of the zone, he’s going to be really tough.”

Continuing in Houck’s process was developing the change-up.

“If you asked me two years ago how do you feel about your change-up, I would have honestly laughed,” he said. “But last year in Salem I really got some confidence with it. I took that into the offseason and built even more confidence with it this year.”

So much confidence that Houck threw more change-ups in his Double-A debut “than in any other game. He got shelled but Houck’s main problem wasn’t executing all his pitches. But he did find some positives.

“I saw weak contact with (the change-up),” he said. “You have to step back and say the results weren’t very good but on the positive side, I got a lot of work in with a pitch that has been questionable.

“Having that work and building that confidence has really moved it forward.”

In his next start, Houck allowed four hits and one earned run. Then on Tuesday — an abbreviated five-inning game because of rain — Houck dominated the Hartford Yard Goats. He retired the first nine batters before allowing a single to left field, Hartford’s only hit. Houck struck out nine, finishing off two batters with his change-up.

“The change-up is getting there and it should be a big weapon for him eventually,” Abbott said. “There are some alignment issues that cause some inconsistencies. That’s gotten better.”

Houck is bound to have more hiccups in the minors but the process is working. Darwinzon Hernandez may not be the only pitcher finding his way to Fenway this season.