Well Bush had a 4.41 ERA in 2006 and Marquis had a 6.02. Relying on a single season of ERA is just about the worst way you could judge a pitcher. Bush is a better K guy than Marquis, he is a better BB guy as well. Marquis induces a lot of ground balls which is his saving grace. If you look at a component ERA type stat like xERA Marquis has been 4.44, 5.21, 4.58 over the past 3 years, Bush has been a 4.23, 3.49, 4.18 which suggests Bush will be a better starter though I'm not convinced he'll ever get over his 1st inning problems or his problems with RISP so my guess is he lives in the 4.50 ERA range which is also what I'd expect out of Marquis. Now if I were going to compare them 1 to 5 this is the way I think makes most sense. #1 Sheets = Zambrano. Sheets is a better pitcher and Zambrano has a 3 year pattern of regression, Zambrano is also a significant injury risk because of his pitch counts over his career so if I had to give the edge to one it would be Sheets. #2 Gallardo = Hill. Both high upside younger pitchers. Hill's age doesn't bother me much because lefties tend to mature late so it is expected. If Gallardo were starting the year healthy I'd give the edge to him but since we don't know how the knee will hold up I ended up calling them even. #4 Suppan = Marquis. Both guys are mediocre innings eaters who will probably sit at a 4.50 ERA or so. If I had to give a slight edge it would be to Suppan but with the Cubs defense I expect Marquis to end up with a better ERA. #5 Bush = Dempster/Lieber. These are all just guys, Bush has the most upside of the bunch at this point since all it would take for him to improve is pitching better with runners on. So at this point we have what I consider four pretty even matchups with the Brewers having maybe a tiny edge in each one. #3 Lilly vs Villanueva. This is the one that will decide things and the one I cannot predict but I think CV has our best chance of being the #3 guy that Lilly is for the Cubs. If CV pitches as well as people expect him to this is a wash, I tend to think that Lilly will win this one and offset the tiny advantages seen in the top 4. #6 Parra > Marshal/Guzman. If this thing goes to a #6 starter the Brewers hold all the cards and in reality Parra is probably better than Lilly/CV though he cannot pitch a full season. If we get to the #7 starters I think the Cubs are holding all the cards because of Capuano's injury. I think the rotations are pretty close overall, if I got to take defense out of the equation I'd give the advantage to the Brewers but since I can't take it out I think things will be pretty even. The Cubs can withstand a major pitching injury better than we can because we released Vargas(assuming somebody picks him up) and Capuano went down for the year(I'm assuming, if he gets better with rest then it is even).