Although he'll be 38 years old by Opening Day next year, Scott Atchison is still arbitration-eligible because he's had limited service time in Major League Baseball. Non-tendered last winter by the Red Sox because of concerns about the health of his elbow, Atchison was signed by the Mets.
In 55 appearances totaling 45.1 innings, Atchison had a 4.37 ERA and 3.75 FIP. The average major league relief pitcher this year had a 3.59 ERA and 3.70 FIP. So Atchison wasn't dreadful, but he certainly wasn't one of the better bullpen arms on the 2013 Mets.
By the estimate at MLB Trade Rumors, Atchison would make roughly $1.3 million next year if he's tendered a contract. With Bobby Parnell, Vic Black, Carlos Torres, Gonzalez Germen, and Jeurys Familia already on the roster, perhaps the Mets will part ways with Atchison simply to give their other right-handed arms a shot, especially if the Mets persuade LaTroy Hawkins to come back for another season. There's a lot of uncertainty among that group, even with Hawkins, though Atchison isn't the only veteran right-handed relief pitcher on the market.