Ryan Zimmerman is at (or near) the end of the 6-year/$100M extension that he signed back in 2012, though the deal does included a club option for 2020 that would pay him the same $18M he’s making this season, unless the Washington Nationals buy it out for $2M.
The expectation, of course, given his injury history, and struggles trying to stay on the field in recent seasons, is that a likely result will be the Nationals buying him out and negotiating a new deal for what would be his 16th major league campaign (or his 14th season in terms of service time), since both sides seem amenable to a deal that would keep him in D.