MIAMI -- As they continue to build from their Minor League system up, the 2019 Marlins used a total of 50 players, including 17 rookies.

With youth comes inconsistencies and growing pains, and Miami certainly had its share during a 57-105 campaign. But lacking experience shouldn’t be confused with lacking talent. The Marlins have some high-end players, many of them getting a taste of the daily rigors of the Major Leagues.

A majority of the players who grinded their way through 2019 project to be part of the future. Still, changes will be made over the offseason. But based on the inventory of players either on the 40-man roster or in the system, MLB.com projects what Miami's roster -- remember, it expands to 26 players in '20 -- might look like on Opening Day.

Catcher
Locks: Jorge Alfaro, Chad Wallach
Possibilities: free agent/trade
Alfaro and Wallach are the only two catchers on the 40-man roster, and both had their ups and downs in 2019. Acquired from the Phillies in the J.T. Realmuto trade, Alfaro was a workhorse, appearing in 130 games and hitting .262/.312/.425 with 18 home runs and 57 RBIs. The 26-year-old is being given every chance to be the team's regular for years to come, but his high strikeout rate (33.1 percent) and inconsistencies behind the plate could change that. Wallach, who made the Opening Day roster as Alfaro’s backup, dealt with concussion issues that limited him to just 19 games. Free agents Austin Romine and Francisco Cervelli could be possibilities. A fallback could be bringing back Bryan Holaday, a free agent who has been with the club the past two seasons.

First base
Locks: Garrett Cooper, Austin Dean
Possibilities: Lewin Diaz, free agent/trade
Cooper was Miami’s Opening Day right fielder in each of the past two seasons, but he ended up playing more first base in 2019. Cooper has the best chance to be a roster lock, starting at first or being a utility man, because he also can play corner outfield. Dean, a left fielder, could find himself as depth at first due to a surplus of young outfielders. The left-handed-hitting Diaz, who hit 27 homers in the Minors this season, is the Marlins No. 12 prospect per MLB Pipeline, and he is worth monitoring. Free agents who could be targets for Miami are José Abreu and Justin Smoak.

Second base
Locks: Isan Díaz
Possibilities: Jon Berti, JT Riddle, free agent/trade
The Marlins did not pick up Starlin Castro’s $16 million club option for 2020, making the 29-year-old a free agent. Still, Miami will be on the hook for a $1 million buyout on his deal. That leaves Díaz as the only viable second-base option on the roster. But the 23-year-old still must earn his roster spot in Spring Training. At Triple-A New Orleans, he hit .305 with 26 home runs and 70 RBIs. But in 49 big league games, he hit .173 with five home runs and 23 RBIs. Infielder Howie Kendrick is a free agent who fits what the Marlins are looking for from a veteran.

Shortstop
Locks: Miguel Rojas, Riddle
Possibilities: Berti, Jazz Chisholm, free agent/trade
Rojas is a veteran presence who has completely bought into what the Marlins are building -- so much so that he signed a two-year, $10.25 million contract extension in September. He will make $5.125 million in 2020 after he hit .284 with five home runs and 46 RBIs in '19. Riddle, who had a down season, is a utility option at shortstop, but his future with the club isn’t secured. Berti could also handle short on occasion. Chisholm, acquired from the D-backs for Zac Gallen, is a power-hitting shortstop option at Double-A, and the general feeling is that he will need a full season at Triple-A before he is ready.

Third base
Locks: Brian Anderson
Possibilities: Rojas, free agent/trade
Anderson’s 2019 season was derailed in late August when he was hit by a pitch and fractured the fifth metacarpal bone on his left hand. He missed the rest of the season. Anderson is an option to play either third base or right field, but third is his natural position. He appeared in 67 games there in 2019, compared to 55 in right field. Anderson hit .261 with 20 home runs and 66 RBIs. With Martín Prado now a free agent, the Marlins don’t have an obvious backup at the hot corner, but Rojas can handle the position.

Outfield
Locks: Berti, Harold Ramirez, Lewis Brinson, Magneuris Sierra, Monte Harrison
Possibilities: Jesús Sánchez, free agent/trade
Berti seized the opportunity in 2019, and he showed that he can handle both the infield and outfield. He may be the front-runner to start off in center field and be the leadoff hitter. Ramirez can handle all three outfield spots, and he showed flashes that he could be a regular with 11 home runs and 50 RBIs. It’s make-or-break time for Brinson, who hit .173 with no home runs in 75 games with the Marlins. He also played 81 games with New Orleans. Sierra is out of options, so he will either make the club or get traded or cut loose. Harrison would have been a September callup if not for right wrist surgery. He’s on the 40-man roster, but if he’s not ready, he would start off at Triple-A.

Starting pitchers
Locks: Sandy Alcantara, Caleb Smith, Pablo López, Elieser Hernandez, Robert Dugger
Possibilities: Jorge Guzman, Nick Neidert, free agent/trades
Miami’s lone All-Star in 2019, Alcantara made major strides, posting a 3.88 ERA while logging 197 1/3 innings. The hard-throwing right-hander pitched far better than his 6-14 record, and he made a case to be the Opening Day starter. Smith was arguably the best starter in the first half before he went on the injured list with left hip inflammation. He had a 3.50 ERA through the All-Star break, but he wore down in the second half with a 5.42 ERA. López missed time with right shoulder inflammation that limited him to 21 starts and 111 1/3 innings. Hernandez is an option for the rotation or bullpen. Dugger showed some promise when he was called up late in the season.

Relievers
Locks: José Ureña, Jarlin García, Ryne Stanek, Tyler Kinley, Adam Conley, Wei-Yin Chen, Austin Brice, Jeff Brigham
Possibilities: Tayron Guerrero, José Quijada, Brian Moran, Kyle Keller
Ureña has a chance to close after being the Opening Day starter the past two seasons, and García was one of the most reliable relievers late in the year. What to do with Chen is another issue; he is making $22 million in the final year of his contract, and right now, he is a long-relief option. Stanek could be used either as an opener or setup reliever and perhaps closer, although that didn’t go so well for him in the second half. Kinley showed promise late, and Conley has plenty to prove after a down year.