Looming 2018 FAs could shrink Orioles' contention window

If the Baltimore Orioles hope to celebrate another championship, they'll need to do it soon.

The Orioles are knocking on the proverbial playoff door loaded with one of MLB's best offensive lineups, consisting of heavyweight sluggers like Manny Machado, Mark Trumbo, and, of course, Chris Davis. It also helps having one of the majors' best bullpens, as the 3.40 ERA posted by their relievers ranked third-best in 2016 behind the Washington Nationals and Los Angeles Dodgers.

But while the Orioles have the pieces needed to contend today, some of their key players are poised to join the 2018 free-agent class, and the farm isn't exactly stacked to replace them.

Here are three impending free agents that could force the Orioles to go all-in now before they're gone, or capitalize on their value in a trade for the future:

Adam Jones

Long their revered and vocal clubhouse leader, Jones may be entering his final seasons at Camden Yards. The center fielder's contract expires in two years, and Jones has chastised the fans in Baltimore for not turning out in proportion to the team's success.

While Jones has carved out a prolific career in Baltimore, the five-time All-Star will be 33 once the winter rolls around in 2018, and his free agency will likely be the last opportunity for him to secure a big-money contract. But, with substantial financial commitments already made to Davis and Trumbo, plus a few other stars entering free agency, the Orioles front office may be unable to keep their veteran leader around.

Zach Britton

Though he began his career with Baltimore as a starter, it wasn't until permanently transitioning to the bullpen in 2014 that Britton began to find success. In 213 career relief innings, Britton owns a 1.35 ERA, but it was in 2016 when he cemented his case as the best closer in the game, converting all 47 of his save opportunities and allowing just four earned runs in 67 innings.

Like Jones, however, Britton is set to enter free agency in 2018. Prior to agreeing on a one-year arrangement for 2017, Baltimore reportedly offered Britton a two-year extension plus a club option earlier this offseason, though he rejected the offer. The 29-year-old has expressed a desire to remain in Baltimore, but with no long-term agreement in place, the Orioles will need to make a decision on their All-Star reliever soon.

Mannny Machado

While Jones has been the Orioles' clubhouse leader, Machado has arguably emerged as the face of the franchise. On the other hand, however, the Orioles will be hard-pressed to keep him around once he becomes a free agent for the first time following the 2018 season.

Despite his free agency being two seasons away, some have already depicted the 24-year-old in New York Yankees gear, thanks to the club's uncharacteristically cheap spending in recent offseasons. Though he won't be alone in that year's free-agent class - Bryce Harper and Josh Donaldson are on pace to join him - it might be near impossible for Baltimore to hold on to its best player.