MIAMI -- With the first season of their organizational buildup in the books, the Marlins enter the offseason with as many questions as answers.
The new ownership group, led by Bruce Sherman and Derek Jeter, made it clear when it took over last October that it intended to build from the Minor Leagues on up. Ownership never wavered from that philosophy, and predictably, the season was filled with growing pains at the big league level. On the Minor League side, there was an increase in their overall depth and quality now in the pipeline.
Manager Don Mattingly and his staff did as much teaching as actually coaching a team that finished last in the National League East. Now that the offseason is here, the front office has many issues to tackle.
MLB.com looks at five pressing questions the Marlins face as they lay the groundwork for 2019.
1. Are the chances of signing J.T. Realmuto to an extension real or will the organization seek to trade their All-Star catcher?
What's next for Realmuto promises to be the No. 1 storyline for the franchise when the Hot Stove season heats up after the World Series. The organization has made it clear that it would like to retain and build around Realmuto, but whether the 27-year-old wants to stay is unclear. What we do know is Realmuto didn't let any distractions negatively impact his play. If anything, the Oklahoma native enjoyed his finest season. To get him to buy in, the Marlins must convince him that the path to winning is sooner rather than later. Realmuto has two more seasons of being arbitration eligible, and the club may opt to keep him as long as possible. But if they get a trade offer that makes sense, parting with the All-Star catcher may be the most realistic option.

2. Stay the course or increase spending?
The organization has been steadfastly consistent about preaching patient and staying the course. Chief Executive Officer Derek Jeter recently repeated that the club will continue to build from the Minor Leagues on up. If that's the case, it sends the signal the Marlins will not be in the market for a big ticket free agent. The big name to South Florida residents is Manny Machado, a Miami native. As impactful as Machado would be to any roster, the timing doesn't appear right to make such a massive financial investment. The Marlins are in the process of building as much organizational depth as possible, and this team is more than a few players away from being a serious playoff contender.
3. Retain or part ways with Dan Straily and Jose Urena?
Urena enters arbitration for the first time in 2019, and he is expected back to front the rotation. Urena finished 9-12 with a 3.98 ERA. In his last seven starts, he was 6-0 with a 1.80 ERA. Straily's situation is a bit different. The veteran will enter his second season of arbitration, and he made $3.37 million in 2018. Straily opened and closed the season with injuries. A right forearm strain landed him on the disabled list in April, and a strained left oblique sidelined him in the final weeks. Straily finished the season making 23 starts, and logging 122 1/3 innings, going 5-6 with a 4.12 ERA. Set for another pay increase, there's a good chance he will be dealt.

4. Are Sandy Alcantara and Lewis Brinson ready to be big league fixtures?
The two showed signs of being big league regulars, but they lacked consistency. Alcantara, the hard-throwing right-hander acquired from the Cardinals for Marcell Ozuna, spent most of the season at Triple-A New Orleans. Alcantara did show flashes of being a top of the rotation candidate, but the 23-year-old also must improve his fastball command. His slider and changeup are works in progress. Brinson, the regular center fielder, spent the entire season in the big leagues. Acquired from the Brewers for Christian Yelich, Brinson missed a couple of months with a bruised hip bone. The 24-year-old showed promise in September, but overall struggled. If he refines his swing, he will stick. If not, he could be a candidate to start at Triple-A New Orleans. The fact he spent the full season in the big leagues saved an option year for the Marlins, should he struggle in '19.

5. Who will fit the mold at first?
Building around athletic players is a central theme, and that's why Justin Bour was dealt to the Phillies in early August. Even though Bour was a left-handed power threat, the slugger didn't ultimately fit the direction the organization is heading. Right now, there is no frontrunner for 2019. In September, Peter O'Brien was a nice story, showing some power. A Miami native who attended the University of Miami, O'Brien was a September callup. But O'Brien is 28, and he's bounced around. Before this year, he last appeared in the big leagues while with Arizona in 2016. Garrett Cooper is another possibility, but he is coming off right wrist surgery. Martin Prado, in the final season of his contract, may see time at first base with Brian Anderson at third base. Otherwise, the position is wide open.