Keep in mind Lilly is out for a month, so there are 2 spots in the rotation to fill. Right now Z, Dempster and Wells are assured spots. Marshall, Shark, Gorz and Silva are fighting for the other two. So even if Silva gets one of those spots, it doesn't mean Gorz and Marshall will both be in the bullpen together. My guess is that Marshall and Silva will get the two spots until Lilly is healthy and then whichever of the former two is pitching worse will be the player that is moved to the pen (thus giving us Z, Lilly, Demp, Wells, Silva/Marshall). That's just a guess, though.