While one can point to many different factors in the Mets’ huge September collapse, one issue that was clear from about May on was that the club simply didn’t have the same sort of pitching depth that they had in 2006. With Guillermo Mota exiled to Milwaukee, the Mets are getting addition by subtraction out of the back end of the bullpen; with Pedro Martinez returning to his post as stalwart ace and Tom Glavine moving on, the Mets face the same problems with the back end of their rotation that they had last year, barring a trade.

My quest for today is simple: find the best candidates that the Mets have signed to minor-league contracts, 40-man-slots, and elsewhere that could make up the back of the pitching staff as of now. With Pedro Martinez and El Duque both likely to be injured at some point—not to mention the fifth starter’s slot currently up for grabs—there are still quite a few innings that need filling. The Mets had a grand total of 38 games started by individuals not named Glavine, Martinez, Hernandez, Maine, and Perez last year. Replace Glavine’s durability with Martinez’s lack thereof, and I’ll guesstimate that the Mets will need at least 50 starts from starters not named Martinez, Hernandez, Perez, and Maine this year.

In the bullpen, Wagner, Heilman, and Feliciano seem good bets to throw at least 60 innings of above-average or better work. However, remember that relievers can fall hard and fast, often without warning—Wagner’s probably the most likely to maintain his success, Feliciano the least. After those three, the Mets’ other relievers combined for 282 1/3 innings, or a little over a full season from a starter. Let’s assume those totals stay the same and the Mets need about five innings a start from the 50 starts that should be up in the air. That’s a little more than 500 innings of baseball that don’t belong to anyone in particular. Obviously if the Mets end up packaging a lot of these guys for Johan Santana or Erik Bedard, that number deflates down to roughly 300, but either way, the back end of the roster is going to be important for the Mets’ chances of success; some relievers to take the heat off of the Big Three would be welcome.

Here’s who are most likely to take those innings and what we might be able to expect. I’ll be supplementing these suppositions with the freely available projections systems from CHONE, Bill James, ZIPS, and the Marcels, which will be giving us some idea of what to expect from everyone.

The Frontrunners

ROTATION

Mike Pelfrey: Pelfrey probably has the inside track on being the Mets’ fifth starter as things stand right now. His standing as a high draft pick and solid minor league track record have kept his career afloat despite inconsistency at the major league level, mainly due to his inability to develop his secondary pitches. I don’t really think Pelfrey is a legitimate option for the rotation at this point. It’s nearly impossible for a starter to survive in the majors with no secondary pitches. However, I do think that, as was the case with many failed starters with good stuff, Pelfrey is a candidate to develop into a quality bullpen arm at some point.

As a starter, Pelfrey has been pegged by CHONE, ZIPS, and Marcel to post an ERA around 4.80.

Phillip Humber: Humber, on the other hand, doesn’t lack the quality secondary pitches needed to become an acceptable starter; instead, the former third overall pick has successfully come back from his Tommy John surgery and performed admirably in the minor leagues. His major problem at this point seems to be the home run ball, giving up 21 last year for New Orleans in only 139 innings. He still had a sterling 120/44 K/BB ratio and allowed less than a hit per inning, but even with Shea minimizing some of his problems with the long ball, moving to the majors could make it an even bigger problem.

Both CHONE and Marcel give Humber better numbers than Pelfrey, with a 4.66 and 4.38 ERA, respectively, although Marcels’ is only for 37 innings. However, ZIPS blows up his ERA all the way to 5.39. At any rate, it’s clear that neither Pelfrey or Humber should be counted on to be above-average in 2008, making the Mets’ attempts to try to find a starter justifiable.

BULLPEN

Duaner Sanchez: Dirty was a force for the Mets in 2006 before the second Mets-related taxi accident in as many years took him out of action with a hairline fracture in his shoulder. Obviously, if he’s healthy, he has the inside track on being a key option for the Mets, perhaps even resuming his eighth inning role. A consistent sub-4 ERA reliever before getting hurt, a healthy Sanchez would do wonders for the Mets bullpen. Any little flaw caused by the surgery, be it a sore spot in the shoulder, a loss of velocity, an adjustment in his delivery, could throw him off. I’m not too optimistic about Sanchez’s chances of being the same pitcher he was, but if he is, it’d go a long way. For what it’s worth, ZIPS, Marcel, and Bill James all have him posting a sub-4 ERA next year with the club.

Scott Schoeneweis: Show is almost guaranteed a roster spot because of his contract. I’m pretty sure he also eats babies. All four projection systems see him as lowering his ERA down to the mid-4.00’s, with a straight 4.50 from James, 4.34 from CHONE, 4.65 from Marcel and 4.34 from ZIPS. I don’t pretend to understand the logic behind these systems, nor will I pretend I can rationally analyze Schoeneweis after last season. Let’s just say I’m skeptical and wouldn’t mind if he was given the Mota treatment.

Jorge Sosa: In an era where it’s commonly accepted that it’s easier to be a reliever than a starter, Sosa bucked the conventional wisdom by going 7-6 with a 4.59 ERA as a starter and 2-2, 4.18 in relief. Sosa grades out about the same as Schoeneweis, with 4.38, 4.33, 4.54, and 4.47 ERA’s from the four projection systems. However, most of these also have him pitching as a starter at some point and putting him in the bullpen full-time may boost those numbers. At any rate, I think it’s safe to say that with his ability to start and relieve, he should probably factor into the back-end of the bullpen in 2008.

Joe Smith: Smith, who baffled the league early on before the Mets sent him back to Triple-A, still managed to finish 2007 with a 123 ERA+ in the majors. After heavy use in April and May, he became very hittable in June and July, when he allowed 26 hits and 11 walks in just 14 2/3 innings. After being sent down to the minors, he came back in September, but had already lost Willie Randolph’s trust; in the little action he saw, the results were as poor as June and July. Was this the case of a rookie pitcher hitting the wall of overuse, or was this the league figuring Smith out?

At any rate, his projections are as follows: 3.66 from ZIPS, 3.65 from CHONE, 4.40 from Marcels.

Waiting in the Wings

Kevin Mulvey: After going 12-10 with a 3.20 ERA and a 113/43 K/BB ratio between Binghamton and New Orleans last year, Mulvey established himself as a threat to break into the rotation sooner rather than later. Only ZIPS has a projection, but it does predict an ERA of 4.17 over 138 innings. Meanwhile, John Maine’s ZIPS projections includes a 4.15 ERA, so it definitely sees Mulvey as a credible pitcher immediately. Omar Minaya has been very quick to rush the prospects he feels are ready, so it will be interesting to see how this plays out, but it’s unlikely he’ll get a crack at the rotation before Pelfrey or Humber.

Juan Padilla: Padilla was successful in 2005, logging 36 1/3 innings with a 1.49 ERA before going under the knife twice, once for Tommy John surgery and a second to repair his flexor tendon. Marcels and ZIPS—the only two systems to offer projections—both give him around a 4.30 ERA. The same caveats to Sanchez apply to Padilla in my mind, but it’s certainly possible he could slot in the back end of the bullpen if everything breaks right.

Steven Register: A fourth-round pick out of Auburn, Register brings a tough sinker after leading the Texas League in saves last year. However, after being taken in the Rule 5 Draft, he doesn’t look like he’s very major-league ready. His career minor league numbers are somewhat pedestrian (1.40 WHIP, 4.64 ERA), and his stuff isn’t anything drool-worthy, either. There are no projections for him, and I expect him to be in Tulsa or perhaps Colorado Springs next April after the Mets send him back to the Rockies.

Matt Wise: A mediocre season pushed Wise from a quality reliever option to someone the Brewers deemed expendable. Many of his troubles last season were attributed to the fact that he broke Pedro Lopez’s cheekbone with a pitch. The Mets are hoping to get the old Wise, and he seems like a good bet to at least be an average reliever. He gets quality projections from everyone, with a 3.83 from both Bill James and CHONE, a 4.34 from Marcel, and a 4.00 from ZIPS. He’s no lock to make the team, but he’s got a better track record than most people who have a chance.

The Others

Steve Schmoll, Wilie Collazo, Carlos Muniz, Jason Vargas, Adam Bostick, Joselo Diaz, Brian Stokes, Ambiorix Burgos

The Mets have a lack of backup options for the starting rotation. Bostick and Vargas are the closest they’ve got, and just about everyone has given up on both. Vargas’ CHONE projection of a 4.70 ERA is the best for either player.

Muniz, Collazo, and Schmoll have all shown flashes of being capable pitchers, but they all have the track records of generic AAA pitchers. CHONE foresees a 4.63 ERA for Collazo over 107 innings, but the Mets seemed reluctant to give him a chance last year as a starter. Stokes and Diaz both seem to fit into this group as well, although Diaz has the better minor league track record and pitched well in Japan last year.

Burgos will likely miss the season following Tommy John surgery.

Conclusion

The Mets seem well-equipped to avoid last year’s bullpen problem. They’ll have a lot of pitchers bouncing back from surgeries and a few others with question marks, but they’ve developed quite a bit of depth, too. And they also still have rumored interest in a few guys like Luis Vizcaino and Octavio Dotel. The rotation, however, looks very thin. That’s not exactly and endorsement of giving someone like Kyle Lohse a lot of money, or for trading the farm for Santana or Bedard, but the Mets could check out a few low-cost options like a Josh Fogg or a Jason Jennings. Given the inevitability of an injury to someone, sometime, they could definitely use a backup plan.