An MRI taken Saturday on Carlos Marmol's injured right hamstring showed only minimal damage. Good news for Marmol and the Cubs. There is no timetable yet for his return, but he may be able to come back after the minimum 15-day stint on the disabled list. Though Rafael Dolis has taken over at closer, it's a role that is likely too see rapid turnover this summer. And Marmol could even work his way back into the mix.