Rosenthal previously lost the closer role for a reason. His ERA was 4.46 with a 1.91 WHIP last year. Yes, a 1.91 WHIP! No wonder they yanked him and experimented with him as a starter. He's at a 3.43 ERA this year, so better. He's 27 and and was good 2013-2015, so I wouldn't mind having Rosenthal, but he's FAR from the answer as a proven closer.