It's really a shame Kirilloff has fallen off after his hot start to the year. I don't particularly care to play him in LF anyway, and Santana should never have been penciled into the starting role vs RHP - should never have been close to that role, really.
Before the season I would have hoped that Yunior Severino would have been ready to be that left-handed 1B if need be, but outside of improving his walk & strikeout rates he's had a dreadful start to the year. Not sure there's anyone in the system right now that could fill that hole.