WASHINGTON -- The Nationals are gearing up for what will be, perhaps, the most important offseason in team history. They believe the 2018 season -- in which they finished 82-80 and missed the postseason -- was an anomaly, a minor setback for an otherwise successful franchise coming off four division titles since 2012. They have eyes on competing for the National League East crown in 2019.
However, the Nats team that takes the field for Opening Day next season will almost certainly look a lot different than this year's team. Here are some of the key decisions and dates that will guide Washington's offseason:
Who will be a free agent?
Bryce Harper will headline not just the Nats' class but will be one of the biggest prizes in all of baseball this offseason. He is joined by Matt Wieters, Greg Holland, Kelvin Herrera and Jeremy Hellickson as players who are set to hit free agency. Remember, the Nats already traded away a few of their impending free agents during the season in Daniel Murphy, Giovany Gonzalez, Matt Adams and Ryan Madson.

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Free agency begins the day after the 2018 World Series ends. Players can begin signing with other clubs five days after that date.
What about club options?
Sean Doolittle has a $6 million team option for 2019, which the Nationals will almost certainly pick up so he can return as closer and anchor their bullpen.
How will this affect payroll flexibility?
The Nationals are going to have some flexibility with their payroll next season, considering the large amount of money freed up by expiring contracts and the cost-saving moves they made before the season ended. They were over the luxury-tax threshold last season and will likely want to get under that number in 2019.
However, that should not stop them from having the freedom to pursue top free agents, especially Harper. If Washington does not sign Harper, it will be interesting to see how they utilize their financial freedom.
Will the Nats make any qualifying offers?
Harper seems likely to be the only player to receive one, which he will easily reject. If Harper signs with another team, the Nats will receive a compensation Draft pick after the fourth round has been completed (mid-100s).
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Who will be arbitration eligible?
The Nats have five arbitration-eligible players, headlined by Anthony Rendon, who is entering the final season of his contract. Tanner Roark, Michael A. Taylor, Joe Ross and Sammy Solis round out the rest of the group.

Are any of those players non-tender candidates?
Solis seems like a prime candidate at this point. He struggled mightily this season with a 6.41 ERA in 56 games, and his inability to retire left-handed hitters became a point of frustration. This is Solis' first season entering arbitration, so perhaps the two sides can work out a deal, but if not the organization will have a decision to make. The deadline is Nov. 30.
When are the Winter Meetings?
Expect an exciting Winter Meetings this season from Dec. 9-13 in Las Vegas -- Harper's hometown, where he will undoubtedly receive a ton of attention.
Injuries/rehabbing players
Howie Kendrick tore his Achilles tendon in April, and while his rehab will continue into the offseason, he should be ready to start the 2019 season on time.
What's on the wish list?
Undoubtedly, Harper's name will be at the top of the Nationals' wish list as they aim to keep the biggest star in team history as a cornerstone.
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But in missing the postseason for the first time since 2015, several flaws were exposed. The Nats will be in the market for a new catcher, second baseman, at least one starting pitcher, and reliable setup men behind Doolittle. Expect the team to use multiple avenues to fill those holes, including free agency, trades and maybe relying on some of their in-house options to take a step forward.