Advancing to the World Series, the Red Sox defeated the National League champion St. Louis Cardinals in six games, to capture the franchise's eighth championship overall and third in ten years.

One at home against the Tampa Bay Rays and another on the road against the Cleveland Indians, resulting in a six-game winning streak which improved their record to 11–4, and put them in first place in the American League East.

However, with the second suspect captured that same evening and Fenway Park under tight security, play resumed Saturday, April 20 with a win of 4–3 by Boston over the Royals (assisted by a go-ahead three-run home run by Daniel Nava).

David Ortiz was bothered by inflammation in both heels during spring training and didn't play in any exhibition games, but he was 2 for 4 in his return, tying the score 1-all with a sixth-inning RBI single off James Shields.

Heading back out on the road, the Red Sox played a 14-inning game on national television as ESPN's Monday Night Baseball covered the 10–8 victory over the Tampa Bay Rays at Tropicana Field.

On July 30, Boston acquired starting pitcher Jake Peavy from the White Sox in a three-way deal, sending infielder José Iglesias to the Tigers and Avisaíl García from Detroit to Chicago.

Buchholz returned to the rotation three months after his last start on June 8 and protected his undefeated season record in game one of a three-game series in St. Peterburg by allowing, with the help of the relievers, no runs.

Back at Fenway Park for the last regular season home stand, Jarrod Saltalamacchia became the third Red Sox player within a week to hit a grand slam, breaking a tie in the seventh against the Yankees, and Koji Uehara set a new franchise record by retiring his 37th consecutive batter.

A day later, the Red Sox secured home field advantage throughout the playoffs thanks to a 7–5 loss by the Oakland A's to the Seattle Mariners, making the last two games virtually pointless.

3:07 p.m. (EDT) at Fenway Park in Boston, Massachusetts The Red Sox had a shaky opening in Game 1, with Jon Lester surrendering solo home runs to Sean Rodriguez and Ben Zobrist.

5:37 p.m. (EDT) at Fenway Park in Boston, Massachusetts David Ortiz had his first multi-home run postseason game to lead the Red Sox to victory, smashing solo blasts in the 1st and 8th innings.

The Red Sox battled back in the top of the 9th inning, tying the game with runners on second and third base, and closer Koji Uehara's efforts retired two batters easily in the bottom of the 9th, until Tampa Bay catcher José Lobatón suddenly crushed a walk-off solo home run.

8:37 p.m. (EDT) at Tropicana Field in St. Petersburg, Florida Starter Jake Peavy pitched 5 2/3 solid innings for Boston, but the Rays got on the board first in the bottom of the fifth with a deep outfield RBI double by David DeJesus.

The Red Sox saved themselves from the embarrassment of being no-hit with a Daniel Nava single in the bottom of the ninth inning, but Boston failed to rally further to make up the one-run gap.

8:00 p.m. (EDT) at Fenway Park in Boston, Massachusetts Tiger pitching again came out strong, with starter Max Scherzer holding the Red Sox hitless through five innings.

In the bottom of the eighth inning, the Red Sox were able to load the bases, and David Ortiz crushed a two-out grand slam to tie the score at 5–5 off the first pitch from new Detroit pitcher Joaquín Benoit.

The home run provided one of the 2013 season's most enduring images, when Tigers outfielder (and Ortiz's close friend) Torii Hunter dove over the wall into the Red Sox' bullpen in an attempt to catch the ball, resulting in his legs being completely vertical while Boston Police officer Steve Horgan lifted his arms in celebration.

Earlier in the day, the New England Patriots had a stunning comeback of their own, with quarterback Tom Brady throwing a touchdown with 5 seconds left to beat the New Orleans Saints at home by a score of 30–27.

The Tigers outhit the Red Sox, and Detroit had several prime scoring opportunities, especially in the first and eighth innings, but all were stanched by effective pitching from starter John Lackey, relievers Craig Breslow and Junichi Tazawa, and closer Koji Uehara.

Although there was still daylight present, Game 3 temporarily ceased in the middle of the second inning due to a light failure at Comerica Park which commenced at 4:42 p.m. EDT and lasted for seventeen minutes.

8:00 p.m. (EDT) at Fenway Park in Boston, Massachusetts The Red Sox scored first, but, with the bases loaded and nobody out, the Tigers took the lead on a two-run single off the Green Monster.

7:30 p.m. (EDT) at Fenway Park in Boston, Massachusetts Jon Lester pitched a gem, going 7 2/3 shutout innings as the Red Sox started early with a bases clearing 3-run double by Mike Napoli in the first.

With the bases loaded with one out and Craig Breslow pitching in relief, Matt Carpenter hit a fly ball to left field, but the runner on third beat the throw home, tying the game.

The Red Sox' subsequent comeback attempts failed, and Cardinals closer Trevor Rosenthal struck out the side in the bottom of the ninth to end the game.

In the bottom of the ninth with one out, Koji Uehara took the mound and gave up a double on his first pitch to Allen Craig which advanced Yadier Molina, who singled earlier in the inning, to third.

In the same inning the first two batters for the Red Sox reached base, a single by Jonny Gomes and a walk by Shane Victorino, but after back-to-back popouts into foul territory by Xander Bogaerts and Stephen Drew, David Ross struck out.

In the top of the fourth, the just awarded AL Golden Glove winner on second base, Dustin Pedroia, committed a fielding error on a possible double play ball with one out and Craig on first.

Cardinals manager Mike Matheny tried to stop the bleeding and replaced his rookie starter with game 4 losing pitcher Lance Lynn, who quickly warmed up after Drew went yard earlier in this inning.

Infielders Coaches Throughout the regular season, numerous Red Sox players sported considerable facial hair, which drew media attention and later drove team marketing.

With time, other players joined, including second baseman Dustin Pedroia; designated hitter David Ortiz; outfielders Mike Carp and Shane Victorino; pitchers Brandon Workman, Ryan Dempster, John Lackey, and Clay Buchholz; and catcher Jarrod Saltalamacchia.