The Yankees tried that for a few games.
Robertson got two chances to save games against the Tampa Bay Rays. In the first one, he loaded the bases before striking out Carlos Pena to end the game and get the save. In the second , Matt Joyce made him pay for putting two runners on, and Robertson surrendered a three-run home run that allowed the Rays to win 4-1 back on May 9.
After starting out at 0.00, Robertson's ERA jumped up to 2.61 as he took the loss and a blown save.
Ever since that game, Yankees manager Joe Girardi has gone with Soriano as the closer, and the results have been significantly better. Not only is Soriano 2-2 in save opportunities, he's made them relatively easy in each appearance.
Soriano's past experience as a closer might make him the better choice to be the interim closer. He dominated as an All-Star closer for the Rays in 2010, and though he struggled in his first season as the setup man for the Yankees, Soriano looks much more comfortable with a year of experience pitching in New York under his belt.
If the Yankees roll with Soriano as the closer without actually naming him as the official one, Robertson can stick to being the dominant setup man for the Yankees, where he has excelled in the past.
Girardi was smart not to dub either Robertson or Soriano as the official closer. If he decides to switch it up should one of them falter, then he's not punishing anyone by stripping away a highly publicized role.
The young Robertson knows he has a bright future pitching in the Yankees bullpen, and he still has a lot to learn. Letting him continue developing in a role with less pressure can only help his career.
Robertson wasn't quite ready to fill Rivera's shoes, and that's fine. Honestly, will anyone ever have that ability? Both Soriano and Robertson know Rivera still holds the official title of Yankees closer until he decides to retire.
While Rivera attempts to get better for 2013, leaving Soriano as the unofficial closer and Robertson as the eighth-inning guy is the best way to go in 2012.
At least for now.