First Pitch: Who replaces Mo?

JUPITER, Fla. -- Mariano Rivera is expected to make it official on Saturday that he is retiring after 2013 season. So who is going to replace him?

We learned it was possible in 2012. Rafael Soriano had as good a regular season as Rivera could been expected to have. Soriano was almost automatic at the end of games handling the pressure of filling Mo’s shoes and filing way the final three outs for the Yankees.

Soriano left behind David Robertson and Joba Chamberlain as Mo's heir apparent. Robertson is the clearly the favorite because he has had the better recent career and he is under Yankee control for next year.

But I wouldn’t necessarily count Chamberlain out. Robertson had only a brief time to take-over for Rivera last year. In fairness, he can’t be judged fully on the small sample size of a couple of outings. But what we saw was a guy that didn’t seem as comfortable in the ninth instead of the eighth.

Chamberlain could be more fearless at the end of games. If he has a big year, the Yankees may have to consider keeping him as a closer. It may be cheaper than trying to sign a Joe Nathan or any other of what shapes as a weak free agent closer market.

UP NOW: Mariano Rivera news and blogs are all over the site. Plus, Mark Teixeira spoke for the first time on Thursday since his injury.

ON DECK: I’ve made the trip back to Tampa because Derek Jeter is expected to speak on Friday. Plus, Andy Pettitte will throw, as well. We will have plenty more on Mo.

QUESTION OF THE DAY: Who do you want to replace Mo?