MIAMI -- Upgrading the offense was the top offseason priority for the Marlins, but if they are to be a surprise playoff contender, pitching will lead the way.

In preparation for the 60-game sprint of a season, the Marlins have loaded up on arms. They are carrying 17 pitchers, including 12 relievers, on their 30-player active roster, which was announced on Thursday.

Miami opens at 7:05 p.m. ET on Friday against the Phillies at Citizens Bank Park.

"As we approached Opening Day, we just looked at the best way to put us in the best position to hit the ground running," Marlins president of baseball operations Michael Hill said. "Our goal is to hit the ground running, and in a sprint of a season, win as many games as possible. We felt like, with the [designated hitter], you can go the 13-position player route at the moment."

Sandy Alcantara will make his first Opening Day start, as he goes up against Phillies right-hander Aaron Nola.

The roster includes six rookies, including four players who have never been on the big league roster, as well as 10 players suiting up for Opening Day for the first time.

In the shortened MLB season, teams will carry 30 players for the first two weeks, and by noon ET on Aug. 6, rosters must be reduced to 28. In the final stretch run, rosters must be set at 26 by noon ET on Aug. 20.

Catcher: Jorge Alfaro, Francisco Cervelli, Chad Wallach
Not that there was much doubt, but Alfaro really cemented the starting spot with a strong Summer Camp. He added a home run in Tuesday’s exhibition at Atlanta, as well. The only question with Alfaro came in Spring Training, when he missed time with an oblique strain. Cervelli, the veteran who is also a mentor to Alfaro, will be the backup. Shortly before Summer Camp, Cervelli had some reservations about playing through the coronavirus pandemic. He stuck it out through camp and will be on an Opening Day roster for the ninth time -- most for any Marlin. Chad Wallach, the primary backup from a year ago, is the third catcher.

First base: Jesús Aguilar
Manager Don Mattingly was recently asked what he likes about Aguilar. The response was basically, everything. Mattingly has admired Aguilar as a player for a couple of years, and he was pleased to see him added to the club. Aguilar could hit either second or cleanup, and he’s expected to play first regularly. Defensively, he has also showed good hands and footwork around first base.

An All-Star with the Brewers in 2018, Aguilar had a down year in '19 with the Brewers and Rays. The Marlins are hopeful he plays more like two years ago, when he belted 35 home runs and drove in 108 runs. In '19, his average was .236 with 12 homers and 50 RBIs.

Second base: Isan Díaz
The organization has high hopes for Díaz, and he will be given every chance to establish himself at second. He made major strides in his development in 2019, batting .305 with 26 home runs and 70 RBIs in 102 games at Triple-A New Orleans. In his Major League debut last August, he homered off Mets ace and two-time reigning National League Cy Young Award winner Jacob deGrom. But overall, Díaz had his struggles in his first two months in the big leagues, hitting .173 with five home runs. The Marlins like Díaz’s swing, and they believe he can be an impactful regular. If Díaz slumps, Jonathan Villar is a candidate to switch from center field to second.

Shortstop: Miguel Rojas
The unofficial captain of the Marlins, Rojas has completely bought into the club’s vision. His leadership has grown through the years, and he commands respect with his work ethic and commitment. Rojas has solidified shortstop, and he actually would be the club’s best defender at all four infield positions. He has played each of them in the past. Rojas hit .284 with five home runs, 46 RBIs, 52 runs and nine stolen bases.

Third base: Brian Anderson
The Marlins feel Anderson is a future All-Star who has the potential to be one of the better third basemen in the NL. The 27-year-old is entering his prime. He showed signs of growing into his power in 2019, when he hit a career-high 20 home runs and recorded an .811 OPS. But his season was cut short in August after he was struck on his left hand by a pitch. How quickly Anderson gets up to speed will be a big factor in whether the Marlins are able to stay in the race.

Outfield: Jonathan Villar, Corey Dickerson, Harold Ramirez
Villar and Dickerson were two key offseason pickups, and they project to start in center and left field, respectively. Villar also could play middle infield, and occasionally serve as the designated hitter. A switch-hitter who played in all 162 games with the Orioles last year, Villar batted .274 with 24 homers, 73 RBIs, 111 runs and 40 stolen bases. Wherever he lines up, he projects to lead off. Dickerson will lock down left field. The 31-year-old was an All-Star with the Rays in 2017, when he connected on 27 home runs.

Ramirez won the job in right field in Summer Camp, but he’s going to have to perform to remain in the lineup. As a rookie last year, Ramirez had the knack for coming up with the big hit, with three walk-offs. For the year, he batted .276 with 11 homers and 50 RBIs.

Utility: Garrett Cooper, Jon Berti, Magneuris Sierra
Cooper provides plenty of value in a multitude of roles. He projects to be used often as the DH, and he also will back up at first base and right field. A year ago, Cooper batted .281 with 15 homers and 50 RBIs. Berti does a bit of everything as a super utility player. He can back up at shortstop, second base and play center field when Villar is getting a breather. Berti paced the club in steals last year with 17. Sierra plays all three outfield positions, and he primarily will be used as a pinch-runner and as a defensive specialist. Sierra is out of options, which means he has to stay on the active roster the entire season or the organization risks losing him.

Starting pitchers: Sandy Alcantara, Caleb Smith, José Ureña, Pablo López, Elieser Hernandez
No surprise on who would get the nod for Opening Day. Alcantara was an All-Star in 2019, logging 197 1/3 innings in 32 starts. The 24-year-old is on the cusp of reaching another level. Rounding out the rotation will be Smith, Ureña, López and Hernandez. There was little doubt about who the first four in the rotation would be, with only the order to be set. The question was the fifth spot, where Hernandez got the nod over Jordan Yamamoto.

“All of these guys have gotten better, and all of these guys have the ability when they step on the mound to go deep into games and give us a chance to win,” Hill said.

Relievers: Brandon Kintzler, Yimi García, Brad Boxberger, Adam Conley, Sterling Sharp, Stephen Tarpley, Ryne Stanek, Alex Vesia, Robert Dugger, Jeff Brigham, Jordan Holloway, Nick Neidert
Figuring out the bullpen was the biggest challenge. And in the end, four of the Marlins’ top 30 prospects, according to MLB Pipeline, will be making the big leagues for the first time: Neidert (No. 10), Holloway (20), Vesia (27) and Sharp (28). Neidert and Holloway have been groomed as starters, but both will be in the bullpen.

“To be on the team on Opening Day, that’s probably one of the coolest things,” Neidert said. “For us four guys who are going to make our Major League debut, that’s extremely exciting. It’s obviously a dream come true. We talked a little bit yesterday after we found out. I honestly didn’t expect to make the team out of Spring Training. I was hopeful that I would get an opportunity throughout the year. This is absolutely incredible.”

Kintzler, who has 49 career saves, is the front-runner to be the closer. García, formerly with the Dodgers, projects to pitch in high-leverage innings. Conley makes it after struggling in a couple of his recent outings. Boxberger, a non-roster invitee, is a potential closing option. There were some health concerns with Stanek (low back tightness) and Brigham (right biceps), but both ended up showing they are ready.

Taxi squad
INF Sean Rodríguez, RHP Aaron Northcraft

Injured list
OF Matt Joyce, OF Lewis Brinson, RHP Drew Steckenrider (60-day IL, which is 45 days in shortened season, with right triceps tendinitis)