The Red Sox build their bullpens unconventionally

There is no single way to construct a bullpen, and sometimes, as the Dodgers and Tigers demonstrated last October, even a team's most earnest relief plans can turn into utter disaster. Committing significant money and years to relievers has long been known as a risky proposition given how volatile relief-pitching performances can be from season to season.

This reality makes bullpen construction something of an inexact science. During Ben Cherington's tenure as general manager, the Red Sox have eschewed spending big money on relievers, preferring instead to make under-the-radar upgrades and develop bullpen arms in-house on the cheap. Yes, trades like the one for established closer Andrew Bailey exist, but those are not the norm for Cherington's Red Sox.

The acquisition of right-hander Anthony Varvaro this past offseason fit this mold to a tee. Varvaro isn't a high-profile arm by any means, but the 30-year-old posted a 2.75 ERA and 135 ERA+ in 123 appearances for the Braves between 2013 and 2014. Meanwhile, all Boston had to give up for Varvaro was mid-level pitching prospect Aaron Kurcz and cash.

Now Varvaro isn't your typical bullpen arm, which might explain why the Red Sox were able to get him so cheaply. He has shown reverse platoon splits throughout his career and held left-handed batters to an impressive .149/.198/.284 mark in 2014. Varvaro uses a fastball that runs away from lefties, mixing in a changeup and curveball to keep hitters off balance. That Varvaro doesn't depend heavily on fastball velocity (although he did average 93.6 mph on his four-seamer in 2014) makes him something of an anomaly in an age when major league bullpens are loaded with hurlers who can light up radar guns.

In fact, the Red Sox bullpen as a whole stands out for this reason. A look at Boston's relief-pitching crop reveals a disparity between the types of relievers the Red Sox employ compared with the rest of the league. In an era when velocity is king, the Red Sox have happily scooped up relievers who don't necessarily throw hard but still get outs, often for a cheaper price than their track record might otherwise indicate.

Koji Uehara is obviously the poster child for this concept. At this point, we've grown accustomed to seeing Uehara sneak 89-mph fastballs by helpless big league batters, but it's worth noting the Red Sox originally landed Uehara on a one-year, $4.25 million contract in free agency that included a team option for another season worth $5 million. Although Uehara had never put up a season-long performance like he did in 2013 for the Red Sox, he had been a solid big league reliever for three years prior to that.

The only attribute Uehara doesn't possess that is typical of dominant major league relievers is, of course, a big fastball, something that can also be said of his fellow relievers in the Boston bullpen, Edward Mujica and Craig Breslow. Mujica himself came to the Red Sox on a rather modest contract last offseason, signing a two-year, $9.5 million deal after an impressive campaign as the Cardinals' closer (and two solid seasons prior to that). His tenure with the Red Sox got off to a rocky start last April, but Mujica quietly finished the season strong, posting a 2.82 ERA and 3.7 strikeout-to-walk ratio in 54 appearances from May 1 onward.

Boston acquired Breslow in a deal prior to the trade deadline back in 2012 for Matt Albers and Scott Podsednik. Sure, Breslow had a tough season in 2014, but he was spectacular in the Red Sox bullpen prior to that and will earn just $2 million this year as he tries to rebound.

This pattern tells us that Cherington and the Red Sox are hesitant to commit any significant portion of the team's payroll (or hand out any long-term contracts) toward relief pitching. Instead, the club's front office has been content to seek deals for underappreciated relievers. While I'd stop short of saying Cherington has exploited an inefficiency in the market for bullpen arms, he has certainly taken advantage of the way pitchers with unconventional skillsets are often viewed.

The Red Sox have been able to produce relievers with big fastballs down on the farm, anyhow, where they make less of a dent on the organization's payroll as they enter the league on rookie-level contracts. Andrew Miller is the obvious example here, and if Matt Barnes ends up carving out a spot in the team's bullpen this season, he could become an overpowering arm Boston can depend on in the late innings.

Cherington's approach to bullpen construction isn't foolproof by any means. There are multiple scenarios that could take place this season in which the Red Sox find themselves devoid of dependable options in the back of the bullpen. Uehara has already begun the year on the DL, and Mujica still needs to prove he can handle a high-leverage workload in a Boston uniform. One can also imagine the loss of Miller looming larger than expected, especially if Robbie Ross doesn't bounce back from his 2014. Plenty of other teams have had success building bullpens in a different manner than the Red Sox. For instance, the Yankees' bullpen, complete with a bevy of hard-throwing arms that includes Andrew Miller, is likely to be formidable this season.

Even still, the club's overall strategy to seek out under-the-radar relievers has served them well in the past and allowed Cherington to allocate more money to players on offense (yay dingers!). An addition like Varvaro is yet another example of Boston finding good value and talent for little cost.

That the Red Sox are able to find an edge in building their bullpen on the cheap allows them to add depth up and down the rest of the roster. Varvaro, like many of his fellow relievers in Boston, is indicative of the creative and shrewd manner in which Cherington assembles the club's bullpen.