While the Mets starting rotation will likely contain several question marks, the bullpen appears to be a revolving door at this point. Two vital pieces from 2010 are likely out, with Hisanori Takahashi heading out west and Pedro Feliciano testing the FA market.

Following the non-tender deadline, many serviceable bullpen arms will become available. Some of these candidates may come on the cheaper side and on short term deals, both aspects the Mets would be looking for.

So here are some internal and external candidates likely to make up the Mets 2011 bullpen.

Despite his issues, K-Rod will likely remain this team’s closer. He is entering the final year of his contract, so he will look to have a big year and put his past behind him. Though he sometimes makes it interesting in the ninth, he still has a little something left in the tank.

Bobby Parnell is another internal candidate who should factor into the bullpen. He has the stuff to be a closer, and this year he could finally develop the confidence to be a consistent late game stopper. He will compete for the eighth inning role this spring.

With Takahashi and Feliciano likely out (though there appears to be a slim chance the Mets can retain Pedro), they are going to need a lefty specialist to deal with the likes of Ryan Howard, Chase Utley and Jason Heyward.

Pat Misch may see some action as a long reliever/swing man. He had some tough luck late last season and actually pitched quite well. As Craig Lerner mentioned, Mike O’Connor, who the Mets just re-signed to a minor league contract, could play the role of lefty specialist. He put up great numbers in Buffalo last year, and a strong spring can solidify his roster spot.

Manny Acosta and Sean Green are some other internal options. Green is awaiting the Mets decision to tender him a contract. They’ll likely sign him but then make it clear to him that he needs to earn a spot during spring training. Acosta is a nice insurance policy, but there are better options.

Ryota Igarashi is still on the roster as well. He had some rough moments last year but might be one of the only viable options.

Finally internally, the thought of Oliver Perez as the lefty specialist is sickening.

After tonight’s deadline, we will know the complete list of non-tenders. As for now, there are some intriguing candidates.

Alfredo Aceves, Matt Albers, Blaine Boyer, Todd Coffey, Bobby Jenks, Hideki Okajima, Jose Veras, Lance Cormier and Zach Miner have already been non-tendered.

George Sherrill, Sean Burnett, Santiago Casilla and Rafael Perez are all non-tender candidates facing tonight’s deadline.

Of these options, Jenks is very appealing and could serve as a set-up man and closer insurance. However, there will probably be a team willing to give Jenks an opportunity at closing. With K-Rod under contract, the Mets could not guarantee that to Jenks.

Sherill and Okajima are only a few seasons removed from dominant performances as lefty relievers. They seemed to have both fallen out of favor with their respected organizations and could benefit the Mets. I’m unsure of what the price tag would be for either of them, but for one year it could be worth it.

None of these other candidates are “can’t miss” options. But the thing about relief pitchers is that anyone can have a breakout season any given year. That’s why teams are reluctant to give long contracts to relievers. One year they can be great and the next they can flop. It could be beneficial to roll the dice with Albers or Cormier.

Assuming the Mets have some cash to add some new faces, here is who I’d like to see in 2011 bullpen. Usually, NL teams carry seven relievers.

K-Rod (closer), Parnell (set-up), Cormier (middle), Okajima (lefty), Igarashi (middle), Misch (long) and an open spring training competition between Acosta, Green and O’Connor.

This bullpen could be just good enough to open some eyes. Then again, it involves some big question marks.