Carson Smith is the Red Sox most underrated move of the offseason

Dave Dombrowski came out of the gate wheeling and dealing, turning over the farm system to reconstruct the pitching core of this team in one offseason. Craig Kimbrel came shipping in from San Diego and the Red Sox plucked David Price out from the top of the free agency pile. Even with just those two additions, the face of the team's pitching staff is almost immediately changed.

Almost immediately, many identified Wade Miley as a candidate to be traded with his consistent numbers and his team-friendly contract. In exchange for Miley, the Red Sox acquired reliever Carson Smith and Roenis Elias. Smith completed his first full season in the majors last year after appearing in nine games in 2014. He was never a highly-heralded prospect nor a reliever who racked up flashy statistics like saves.

But Smith's potential on this Red Sox has the potential to be as great as that of almost anyone else in the bullpen, which makes him the team's most underrated move this offseason. Here are three reasons why.

Well, he was really damn good last year.

Objectively, Smith put up some of the most impressive peripheral statistics among relievers last season. The 26-year-old struck out 11.8 batters per nine innings while posting a BB/9 under three per nine and a WHIP of 1.01. Additionally, Smith ranked 11th in baseball in K% (32 percent) and 15th in K-BB% (25 percent). And while ERA or FIP aren't great measures of how well reliever is performing, Smith did post an impressive 2.31 ERA and 2.12 FIP last season.

And hey, if you do care about saves, Smith posted 13 of those while Fernando Rodney had his now-annual implosion while closing for the Mariners last season. Smith brings a 93 mph heater and a nasty slider to the table. The two-pitch mix proves to be devastating in practice.

If Carson Smith striking out Mike Trout on a nasty slider doesn’t get you pumped as a #RedSox fan, nothing will. pic.twitter.com/PLvExeXaS8

— Joon Lee (@iamjoonlee) December 7, 2015

Last season, Smith's slider was as hard to hit as a Best Picture prediction for this year's Oscars. Right-handers hit just .169 off the pitch, with lefties coming in at .227. Even Mike Trout doesn't know what to do with himself after facing off against Smith's slider.

The Ripple Effect on the Bullpen

Let's face the facts: Koji Uehara is old and coming off an injury, we don't really know what to expect out of him. Junichi Tazawa practically had his arm fall off the last two seasons due to the number of high-leverage situations he's had to appear in: There's a reason why Tazawa's arsenal completely lost life in the latter part of 2015. Smith, presumably taking over the 7th or 8th inning, assumes some of the ridiculous number of innings Tazawa took on last season.

It's been difficult for Red Sox manager John Farrell to trust any pitcher out of the bullpen other than Tazawa or Uehara the last couple of years, essentially making them the go-to option should anything go wrong ever. If all things go as planned for the Red Sox, the team now has four pitchers it can rely on consistently to get big outs, with Kimbrel and Smith highlighting the last two innings of games.

Farrell's been criticized for his use of the bullpen over the last few seasons, but he's never had an arsenal of pitchers that look as good as this trio, on paper. Following the Royals as a blueprint, expect Smith to expand the flexibility within which the team can bring out their big guns out of the bullpen in the late innings of close games.

He's not even arbitration eligible until 2018

This is the part that makes the least sense to me from the Mariners' side of things. Yes, relievers are more mercurial than most. Just ask 2015 Craig Breslow of what he thinks about himself in 2013. But even so, Smith put together one of the best seasons among relievers last year and, at 26 years old, presumably has room to grow.

The fact that Smith has room to grow as a reliever is scary, and especially pertinent given that the team has him under control through his age 30 season in 2020. If Smith is able to sustain or provide 80-90 percent of what he did last season while he's still cost-controlled, the Red Sox will have themselves one of the biggest bargains in baseball among relievers, whose cost have risen and risen exponentially over the last couple of seasons.

The others

There are a few other players that you could consider, although it's hard call Price or Kimbrel "underrated." Chris Young certainly can't be ignored, which Matt Colllins covered in this space a couple of weeks ago. There's also Roenis Elias or any of the other minor league players the Red Sox signed and invited to spring training including Anthony Varvaro, Ryan LaMarre, Brennan Boesch, Ali Solis, Ryan LaMarre and Dan Butler. Smith, however, figures to have the biggest impact considering his relative unknown status among top-flight relievers.