Marmol reminds me of Dempster when he closed, but the problem is that this problem has gone on for longer than a year. He is an awful player. No one is afraid of his slider. Where's the command? Where's the confidence? Just get rid of him.
Except he was really, really good in May, June, August, and September of last year. He had a rough start and a really bad July.
I'm afraid he's never going to prove he's quality. The best case is that he will prove he can get the job done a reasonable amount of time and just give everyone a heart attack every time he does that. He'll be a poor man's Papelbon in that regard.