J.D. Martinez, now a member of the Boston Red Sox, hit .303 with a 1.066 OPS between his time with the Detroit Tigers and Arizona Diamondbacks last season. (Mark J. Terrill/Associated Press)

The Boston Red Sox agreed to a five-year, $110 million deal with designated hitter J.D. Martinez, giving them the free agent slugger they needed to keep up with their divisional rival, the New York Yankees, after the Bronx Bombers acquired Giancarlo Stanton, the 2017 National League MVP and one of the best right-handed power hitters in the game, from the Miami Marlins.

Martinez hit .303 with a 1.066 OPS between his time with the Detroit Tigers and Arizona Diamondbacks last season, catching fire in September by batting .404 (40-for-99) with 16 home runs (tying a NL record). His overall run production rate was 66 percent higher than the league average after accounting for league and park effects (166 wRC+). Only AL rookie of the year Aaron Judge of the New York Yankees (173 wRC+) and Mike Trout of the Los Angeles Angels (181 wRC+) were better in 2017.

Judge was also the only batter better at hitting the ball on the sweet spot, also know as a “barrel,” in 2017. Martinez averaged a barrel once every 12.3 plate appearances, just a few whiskers behind Judge (12.7) for the best rate in baseball. Plus, as a right-handed hitter, Martinez could benefit from the Green Monster when batting at Fenway Park; his spray chart suggests the 30-year-old would have hit six more home runs at home if he wore a Red Sox uniform all of last season, a welcome addition to a team that hit 168 home runs in 2017, placing it last in the AL in homers for the first time since 1993.

According to FanGraphs’ preseason projections, Martinez is expected to hit .287 with 39 home runs in 2018, producing 3.4 wins above replacement, making him the second-most valuable hitter on the team after outfielder and leadoff hitter Mookie Betts. Right behind Martinez is shortstop Xander Bogaerts (3.4 fWAR) and outfielder Jackie Bradley Jr. (3.2 fWAR), giving Boston a formidable presence at the top of the order.

1 Mookie Betts RF 0.298 0.366 0.505 0.871 5.5
2 Andrew Benintendi LF 0.284 0.357 0.460 0.817 2.9
3 Xander Bogaerts SS 0.287 0.350 0.440 0.790 3.4
4 J.D. Martinez DH 0.287 0.356 0.575 0.931 3.4
5 Hanley Ramirez/Mitch Moreland 1B 0.261 0.333 0.453 0.786 0.7
6 Rafael Devers 3B 0.280 0.331 0.485 0.816 2.6
7 Eduardo Nunez 2B 0.291 0.326 0.436 0.761 1.0
8 Jackie Bradley Jr. CF 0.257 0.335 0.440 0.775 3.2
9 Christian Vazquez C 0.260 0.311 0.372 0.683 1.4

FanGraphs projects Boston’s hitters, including bench players, to produce 27.7 fWAR in 2018, giving the Red Sox the third-best collection of hitters in the majors next season. The Yankees, even after the acquisition of Stanton, rank sixth (26.4 fWAR).

Martinez’s signing also puts the Red Sox-Yankees rivalry front and center, with the teams going head-to-head to compete for the AL East Division title. At the time of the Stanton trade, the Red Sox were estimated to finish the regular season with a 91-71 record, one win behind the Yankees. Now, Boston is projected to have just as many wins as the Bronx Bombers.

AL East, 2018 projection G W L
Yankees 162 93 69
Red Sox 162 93 69
Blue Jays 162 86 76
Rays 162 80 82
Orioles 162 75 87