Red Sox trade Travis Shaw, Mauricio Dubon to Brewers for Tyler Thornburg

The Red Sox have traded Travis Shaw, Mauricio Dubon, and Josh Pennington to the Milwaukee Brewers in exchange for reliever Tyler Thornburg. Evan Drellich had the news of the deal and Dubon first, with Alex Speier first on Shaw’s inclusion, Ken Rosenthal on Thornburg and Josh Norris on Pennington.

The Red Sox have their relief help. In 2016, Thornburg pitched to a 2.15 ERA in 67 innings of work, striking out 12 batters per nine innings and amassing 2.0 fWAR and 2.5 rWAR. That, for the record, is some ridiculous value for a reliever. He’s a fastball-curveball-changeup guy, with all three pitches grading out positively over the course of his career. The big difference of late seems to be both a jump in velocity—he’s up into the mid-90s after spending 2015 recovering from an elbow injury—and his changeup shining in a reduced role as he’s able to rely more heavily on heat to get ahead.

They’re not just getting Thornburg for 2017, either. He’s under team control for three more years, with this his first season in arbitration. While Carson Smith’s injury makes the comparison a bit awkward, the Sox have done a good job of setting themselves up for some longer-term stability in the bullpen.

The cost for the Red Sox is not small, but it’s also not hugely significant. Travis Shaw was one of a dozen equally uncertain options the Red Sox had at third base. He was arguably the first in line based on incumbency, but the Sox were certainly not expecting any one of their options to be the answer, at least not until Yoan Moncada gets in a good run in Triple-A. Mauricio Dubon, too, was one of those options, and if he was one of the last in line, his breakout 2016 season at least made him one with decent upside. Josh Pennington is the afterthought here, but could turn out to be another Thornburg years from now in much the same way half the pitchers in short-season ball could. That’s just the way 20-year-old pitchers work, aside from a very select few.

These are players who, one day, might make the Red Sox regret doing business here. But if you’re not willing to engage on this level of risk, you’re basically committing to no trades, ever. The Sox could easily stomach these costs, and Tyler Thornburg is a very real boost to a bullpen that needed at least one strong addition. With his salary likely to come in fairly low in his first year of arbitration, it also gives the Sox a chance to invest further in the relief corps (I keep returning to the idea of bringing back Brad Ziegler, who was such a perfect fit for them) and perhaps a bit of wiggle room at DH. With Shaw out of the mix as even a left-handed platoon partner, this move does suggest the Sox will add some bat to their roster. Just don’t expect this to be the harbinger of an Edwin Encarnacion deal. The gap there is much wider than the price of a reliever.