I agree Hays might be out all year. But he also might just need to be hooked up to an IV for a few days and will be back.
That said, I don't know what Callison is seeing in him. He has not hit RHP much better than Marsh hits LHP. It would be a loss to not have him in the LF with Marsh, platoon; it's more of a plus than a minus to go back to the Marsh/Rojas OF against RHP every day.
What would be ironic (if unfortunate for Hays) is if he ends up being out and Wilson continues to be just as good an option (again, just in the platoon role).
Merrifield and Soto were All-Stars too.