Marsh has been a good Phillies player for 2 1/2 years and a struggling one for 1 month. It doesn't matter that he can't hit lefties, even if it would be nice. But with Rojas in the platoon, he doesn't have to. And he is an acceptable CF, not a mediocre one. Mistake by the Phillies to move him off LF in the first place (both for Hays and Kepler, who can't hit LHP either, so they still need both Rojas and Wilson either way). There was no special off-season mandate for him to improve, any more than every other player on this roster was asked to improve things (from our RF to our 3B to our SS).
It would still be great if Crawford came up and took the job. But would be better if Marsh also gets back to his previous form. He's still young and cheap and would be a candidate to go back to LF next year, or they could trade him. Can't trade him now though. And I'm still not convinced Crawford would be the answer if rushed (more like a repeat of Marsh with the Angels and Rojas with us)