According to Adam Rubin, Terry Collins acknowledged today that reliever Manny Acosta, who is out of minor league options, is “all but a lock” for the Opening Day roster in the bullpen along with Frank Francisco, Jon RauchRamon Ramirez and Tim Byrdak.

After being retained on the 40-man roster at the expense of losing former top prospect Fernando Martinez, D.J. Carrasco has an excellent shot of coming up north rather than being designated for assignment. That would certainly conjure up a hornet’s nest for the Mets who don’t want anymore negative attention.

This creates a fierce competition for the remaining spot in the pen between Pedro Beato, Daniel Herrera, Chuck James and Bobby Parnell. Youngsters Jenrry Mejia and Robert Carson could also figure into the mix if they impress in camp.

Regarding Parnell and the other candidates, Collins is looking for an immediate impact this spring:

“When we start playing games, I want to see some consistency … to where their command isn’t erratic in the beginning and you’re saying, ‘He’s going to be OK.’ From the get-go, I want to see some good outings.”

One thing to also remember is that Parnell still has one minor league option remaining and that could also play a factor.