Chicago Cubs: What does Darvish bring to the table?
An easy answer would be six-man rotation. If Darvish comes back, and the Cubs have a tough stretch of games in late August and September without many off days, a six-man rotation makes sense. Joe Maddon has done that in the past and is somewhat expected anyway these days.
Now, it may not necessarily play out that way. Obviously injuries could change the course, but also consider Mike Montgomery. After a good start to his string of starts in late-May and June, he has struggled in July with a 5.57 ERA and .360 average against.
He has not started games consecutively this long in his career, so if struggles continue, moving him back to the pen could happen. Right now he is in the rotation still because of the Chatwood struggles. Darvish returns, he is the odd man out if they do not go with six guys.