Martin may still be a productive catcher in 2019 at 36, but if you really believe Kyle Schwarber is your future behind the plate, there's no reason to wait until 2020 to find out. Maybe the Cubs truly believe Schwarber will become a left fielder and they'll have to get another catcher anyway, as many surmise. But they keep insisting Schwarber can catch in the majors, so why risk blocking his path in 2017 or '18?