Who's going to step up?

The starting rotation became less cloudy today when it was revealed that 
Chris Cappuano's ailing elbow needs a second 'Tommy John' surgical 
procedure. After Sheet and Soupcan, who are the 3, 4, and 5 pitchers?

One month into the season, here's what I see:
1. Sheets
2. Soup
3. Gallardo
4. Villanueva
5. Bush