according to the BTV site..Plesac would be an overpay..
Additionally.. Mark Feinsand had this to say (at MLB.com)
Mitch Haniger, RF (Mariners)
Under club control through 2022
The Mariners are looking to build on their 90-win season, and with the Astros potentially taking a step back following the loss of Carlos Correa, Seattle has its sights set on its first trip to the postseason since 2001. That said, the Mariners’ strength is in the outfield, having added Jesse Winker to a group that includes Haniger, Jarred Kelenic and top prospect Julio Rodríguez. If Rodríguez gets to the Majors and shows he can handle an everyday workload, GM Jerry Dipoto could look to move Haniger -- who will be a free agent after the season -- in an effort to fill another hole on the roster.
That hole being their starting pitching..