We really have to hope Devers and or Shaw can step in without a significant loss in production (from HanRam-Pablo). Then, there is Swihart, who could become a force at 1B, DH or even 3B, if catcher does not work out. He could also be a trading chip, if we don't need him at catcher.
If Groome can be a solid 4-5 starter by 2020, that could allow us to maybe get by with just bringing back (or replacing in kind) Porcello or Sale. That hope also depends on ERod and Wright stepping into the 3-4 slots adequately.
Probably, a more realistic approach would be to hope 2 of the 3 (Devers, Groome & Shaw) come through for us. I guess an added hope could be that we get a pleasant surprise from Dalbec, Hernandez, Ockimey, Chatham, Longhi or someone else, but I wouldn't hold my breath on that.
We may have to hope Owens or Johnson can replace Pomeranz after 2018 as the 5/6th starter. Travis can replace Moreland after this year or Devers could replace Moreland as Pablo moves to 1B or DH after 2017. We should know enough about Devers and Travis after 2019. Keeping 3B/1B/DH low cost positions would go a long way in our hopes of keeping just about all the guys we want to keep.