Which of the taxi squad relievers has the best chance to stick in the bigs?

One of the more creative ways the Yankees have worked around the limitations of a 25-man roster this season was using a flurry of moves to bring relievers up and down from Triple-A Scranton. It seemed every day there was news of someone being optioned or designated for assignment and another player being recalled to the big leagues.

The primary members of this taxi squad were Branden Pinder, Nick Rumbelow, Bryan Mitchell, and Nick Goody. They're now all in the majors with the September roster expansions. They've been joined this time by Caleb Cotham, who had a few abbreviated cameos prior to September, and new face James Pazos. The Yankees have historically been quite good at churning out relievers, and this year they hit a goldmine in terms of sheer volume. The group have had varying degrees of success and failure this season, which is to be expected when it comes to rookies.

All of them have good stuff at the very least, and it makes one wonder which of these rookie pitchers has the best chance to stick around for a while in the big leagues. Herein we'll take a look at each of them and consider their long-term viability.

Caleb Cotham

Cotham was a fifth round pick in the 2009 draft that also produced Mitchell, Shane Greene, John Ryan Murphy, Slade Heathcott, and Adam Warren. He bounced between starting and relief work for a long time, never finding success anywhere until moving into solely bullpen work this year. At age 27, Cotham is old for a rookie but it's not completely jarring to see a reliever make his debut at this age.

Given what we've seen, Cotham doesn't seem to rate as anything more than an up-and-down depth arm. He's only thrown 5.2 innings in the big leagues so far, but I've had a few looks at him in the minor leagues and his stuff has never impressed me. He'll be useful to the Yankees moving forward because he can be optioned to the minors a few more times, but it also wouldn't be shocking to see him bounce around a few different organizations. Cotham should be commended for reaching the Majors, yet he may prove to be a Quad-A type in the end.

Bryan Mitchell

The story on Mitchell is fairly well known by now. A starter through his minor league career, Mitchell's combination of big time velocity and control issues have lead many to believe his stuff would be better suited to the bullpen. Perhaps because of a relative unfamiliarity with bullpen work and being tasked with getting big league hitters out, Mitchell was worked to a 5.47 ERA in 24.2 innings this year. 13 of his 15 appearances have been in relief.

There have been times where Mitchell has looked excellent (his extended extra-inning relief appearance against Cleveland) and times where he's looked completely lost (his recent outing against Toronto). I chalk that up to relative inexperience and the transition to the bullpen. I do believe Mitchell is a reliever in the long run, and with time he could become a true asset. He has truly nasty stuff (see below), and his ability to pitch multiple innings is an underrated quality. Below the ugly ERA lies a 3.83 FIP that probably improves as he works at becoming a reliever full-time.

Nick Goody

I'm one of the biggest Nick Goody proponents out there for a reason. Though he doesn't posses eye-popping heat like Mitchell, Goody consistently recorded big strikeout rates in the minors this year. He struck out 34.5 percent of the opposition at Double-A, and 30.5 percent at Triple-A.

His issue in the very brief 3.2 innings he's seen in the Majors has been a lack of command with his secondary offerings. This didn't show up nearly as much in the minor leagues, and it could be a result of fatigue (he only threw 31.1 innings last year and has reached 65 so far this season). I've seen Goody make legitimate big-time prospects look absolutely silly, and I'm still holding out hope he can translate that success to Yankee Stadium.

James Pazos

Pazos is a big left-hander who's shot through the system after being taken in the 2012 draft. He works effectively against both right-handed and left-handed hitters and could quite easily become a Chasen Shreve-type who can be deployed regardless of who's coming up. He's only thrown 2.1 innings in the big leagues so far, but there's no denying his stuff. He's been clocked as high as 96 MPH and that kind of velocity is always welcome from a southpaw. Spring training and the early months of next season should offer a better look at him versus major league hitters.

Branden Pinder

Pinder is a prototypical power reliever. He throws hard, strikes guys out, and occasionally gets dusted up for a monster home run. He's averaging 1.40 home runs per nine innings pitched in the majors thus far. Control issues are the cause of that, as well as his 3.51 BB/9. Shaky control is to be expected from a young depth reliever but on the whole Pinder has been decently useful as an up-and-down spare arm. I wouldn't expect him to seriously challenge for an Opening Day spot next year, of course, but the Yankees could do much worse for quality relief depth than Pinder. These kinds of pitchers have value in that they can step into a front end spot in the big league bullpen and can actually be trusted with mid-level leverage situations.

Nick Rumbelow

Rumbelow is largely in the same category as Pinder as a righty middle relief/setup type, but his stuff is better than Pinder's. His breaking ball can be very good, and when he locates his fastball it makes the breaking ball that much more dangerous. His exaggerated over-the-top delivery also provides more deception on his pitches. With more polish it's not hard to imagine Rumbelow becoming a setup man somewhere in the big leagues. He's posted dazzling strikeout rates all through the minors and while so far his rate is only 7.11 strikeouts per nine innings in the big leagues, that's once again the adjustment period speaking. Watching what Rumbelow accomplishes in his time in the Bronx next year will be very fascinating.

In summation, there isn't a dazzling future relief ace in this group. There's no David Robertson here, and the list doesn't include the injured Jacob Lindgren. Yet almost all these pitchers have the chance to be useful relief arms, be it for the Yankees or for a different organization after the winter's trades have been made. This list also does not include relief prospects such as Triple-A's Johnny Barbato or some of the flamethrowers kicking around in the low minors. The Yankees have always been good at producing relievers, and these young guns are the latest crop. In other organizations, almost all of them would have consistent big league jobs. Because of the names above them on the depth chart (Betances, Miller, Wilson, Shreve, Warren, etc.), they've been relegated to the taxi squad. It's a good problem to have, to be sure, and next year will be their chance to prove themselves on a more consistent basis.

Nicolas Stellini is a staff writer at Pinstripe Alley, where he writes about the Yankees and covers the Double-A Trenton Thunder. His national coverage can be found at Beyond the Box Score. You can follow him on Twitter at @StelliniTweets.