MIAMI -- When the Marlins acquired Sandy Alcantara from the Cardinals at the 2017 Winter Meetings, the organization envisioned him being a potential top-of-the-rotation candidate.

• 2019 All-Star Game, presented by Mastercard: July 9 at 7:30 p.m. ET on FOX

In his second year with Miami, and in his first full big league season, the hard-throwing right-hander has emerged as an All-Star.

All-Star rosters were announced on Sunday night, and Alcantara was selected to the National League squad. The 23-year-old is the Marlins’ lone representative.

“I'm really happy for Sandy,” Marlins manager Don Mattingly said. “He's a kid that we feel is getting better through the course of the season, from last year to this year. We still feel like this is the tip of the iceberg for him. Hopefully, it's one of many.”

The Marlins are in the midst of a building process that is revolving around starting pitching. Alcantara is one of the faces of what the team hopes will remain a strength for years to come.

"I watched the All-Star Game all the time," said Alcantara of growing up in the Dominican Republic. "To see the guys who represented their teams and represented their countries, I want to do that too."

In 16 starts, Alcantara is 4-7 with a 3.86 ERA.

He is a hard-throwing righty whose four-seam fastball averages 95.4 mph, according to Statcast. His hard-hit percentage is 32 percent, lower than the MLB average of 34.3 percent.

“I'm happy for guys when they make that first All-Star Game,” Mattingly said. “It's a great feeling for them.”

Alcantara was a centerpiece in the Marlins' deal with the Cardinals in December 2017 for outfielder Marcell Ozuna. Miami also landed right-hander Zac Gallen, outfielder Magneuris Sierra and left-hander Daniel Castano in the trade.

Alcantara and Gallen, ranked by MLB Pipeline as Miami’s No. 9 prospect, are currently part of the rotation.

Gallen recalls the first time he saw Alcantara pitch. It was in 2017 at Double-A Springfield. Just called up, Gallen sat in the stands, charting pitches for Alcantara.

“The first time I saw Sandy was actually kind of funny,” Gallen said. “When I got called up to Double-A in 2017, he was actually pitching that night. When I got in, it was a long flight. I actually had chart duty in the stands. I was sitting there. I knew about Sandy, but I had never seen him pitch.

“He was 100-102 [mph] in the first inning. I was like, 'Holy smokes!' With all kinds of movement. It was cool. I've known Sandy since 2017. It's cool seeing how he's progressed.”

The past few seasons, the Marlins have parted with All-Star players, like Ozuna. In return, they believe they’ve accumulated numerous prospects who project to be fixtures in their building process.

Alcantara is the first of the group to achieve All-Star status. He is the fifth Marlins' rookie to be named to the All-Star Game, joining Alex Gonzalez (1999), Dontrelle Willis (2003), Dan Uggla (2006) and Jose Fernandez (2013).

“It's awesome,” Gallen said. “I know a lot of people thought that trade wasn't going to produce what it did. Something like that shows it's producing earlier than people thought. I think it's awesome for him. He worked hard. He's still working hard. It's good he was rewarded for that.”

The 2019 All-Star Game presented by Mastercard will be played on Tuesday, July 9, at Progressive Field in Cleveland. It will be televised nationally by FOX Sports; in Canada by Rogers Sportsnet and RDS; and worldwide by partners in more than 180 countries. FOX Deportes will provide Spanish-language coverage in the United States, while ESPN Radio and ESPN Radio Deportes will provide exclusive national radio coverage. MLB Network, MLB.com and SiriusXM also will provide comprehensive All-Star Week coverage.

A native of Azua in the Dominican Republic, Alcantara made his MLB debut with the Cardinals on Sept. 3, 2017. He made eight relief appearances in St. Louis before being dealt to the Marlins.

In 2018, his first season with the Marlins, Alcantara spent most of the year at Triple-A New Orleans. He made six starts for Miami, and was 2-3 with a 3.44 ERA.

Alcantara’s highlight performance this season came on May 19 against the Mets, where he tossed the only complete game so far this year by a Marlins’ starter -- and gave up two hits.

In his last start, a loss to the Nationals, he was charged with six runs in six innings, giving up five of those runs in the sixth. After that outing, he didn’t think an All-Star appearance was realistic.

“In my last outing, I gave up a couple of runs,” Alcantara said. “Then, I said, 'Oh, I lost my [chances] to go to the All-Star Game.' But I never gave up. I just do my thing, and awaited my opportunity. It's really important. This is my first time. I've got to go there and try to do my best and represent my team.”