JUPITER, Fla. -- On the first day of Spring Training, Marlins manager Don Mattingly quipped that everyone had picked his club to finish fourth or fifth in the National League East in 2021 -- despite its success in 2020. After reaching the playoffs for the first time in 17 years, then upsetting the Cubs in the NL Wild Card Series, the Marlins will now be tasked with the Majors' toughest division across a 162-game slate.

"We've still got a lot to prove, and obviously this division has stacked up," Mattingly said during a Zoom call. "The Braves really have been the team that's kind of had everybody's number. Now it seems like everybody's loading up. I think we will be more confident moving forward because of what happened last year. I think that was good for our players. But I don't think that we're going to come in overconfident, and we know we've got a lot to prove."

The landscape has changed, with no universal designated hitter or expanded playoffs. Only five NL clubs will play deeper into October. For new general manager Kim Ng, the expectations are simple: The Marlins will come to the ballpark and be competitive on a daily basis, with a chance to win each game.

"I think we've got a good mix of veterans and young players, and I look for the veterans to stabilize us, and I look for the young players to come in and really try and figure out how they can be consistent on an everyday basis," Ng said. "When that happens, that's progress, and that's improvement. And that's what we need from these young guys."

With Opening Day scheduled for Thursday at 4:10 p.m. ET against the reigning American League champion Rays at Marlins Park, here's a preview of what's ahead for the Marlins in 2021.

What needs to go right?
The Marlins' strength lies in their starting pitching, which is the main reason why the ballclub has so much optimism entering the season. But the rotation is very young and lacks big league innings. The projected staff of Sandy Alcantara, Pablo López, Elieser Hernandez, Sánchez and Trevor Rogers are all 25 years old or younger, with a combined 128 MLB starts. After a truncated 2020 schedule, it is unclear how their arms will hold up over a long season. The organization has a plan in place to ensure Sánchez and others can pitch into September despite innings limits. In a perfect scenario, everyone stays healthy and pitches according to the plan.

Great unknown
It would be too easy to go with the starting pitching, so how about the relief corps? Miami made it an offseason priority to revamp its beleaguered bullpen, which had a 5.50 ERA in 2020. The club added strikethrowers with postseason experience in Anthony Bass, Dylan Floro, John Curtiss, Ross Detwiler and Adam Cimber. Floro and Curtiss even competed against each other in last fall's World Series. This group won't accumulate strikeouts, so the hope is that the defense will play well behind the relievers. With more depth than in years past to prevent overtaxing pitchers, the Marlins hope it will be enough to win more close games.

Prospect to watch
Take your pick. MLB Pipeline recently unveiled its latest top 30 prospects rankings for Miami's fourth-ranked system, and it's possible the first nine could all play in big league games sometime in 2021. Jazz Chisholm (No. 66 overall prospect in MLB) will be the starting second baseman, and he showcased athleticism across all facets of the game during Spring Training. Sánchez (No. 15 in MLB) also could impact the season from the very beginning, depending on whether he's built up enough to make the Opening Day rotation. In 2020, Sánchez flashed frontline starter stuff during his highly anticipated first taste of The Show. Both have the potential to be marketable stars and must-see viewing.

Team MVP will be …
When the Marlins traded for veteran Starling Marte last August, they did so with the intention of exercising his club option. A two-time Gold Glove Award winner, the All-Star solidified center field and the top part of the order during Miami's stretch run. Throughout Spring Training, members of the front office and coaching staff -- as well as teammates -- haven't shied away from saying how eager they are to see a full season of Marte. With a blend of speed and power, he should be a 20-20 guy. Perhaps the 32-year-old can even record the franchise's first cycle?

Team Cy Young will be ...
With all due respect to my colleagues, Alcantara is the club's ace until someone supplants him. The right-hander continues to improve every season, particularly when it comes to his command. In his first full campaign in 2019, not only did Alcantara make the All-Star team, but he also tied for an MLB-high two shutouts and finished with 197 1/3 innings. That durability will be pivotal in the return to a marathon season. When camp began, Alcantara made it known he wanted to be the leader of the staff. Three weeks later, he was named the Opening Day starter for a second straight year.

Bold prediction
How bold are we talking? With a relatively clean bill of health on the pitching side, the Marlins will do just enough on offense to once again shock pundits by reaching the postseason for the second straight year. It turns out that the combination of a young starting staff, a veteran-laden lineup, an experienced bullpen and a deep farm system can win enough close games to secure a Wild Card berth. Was that too bold?

If they don’t end up making the postseason, Miami will at least be part of the playoff chase into August, when pitching typically begins to wear down during a long season.