The 2021 Boston Red Sox season was the 121st season in the team's history, and their 110th season at Fenway Park. The team entered the offseason conducting a managerial search, after declining to bring back Ron Roenicke from the shortened 2020 season. On November 6, 2020, the team re-hired Alex Cora as manager; Cora had skippered the Red Sox in 2018 and 2019, then sat out 2020 serving a one-year suspension for his role in the Houston Astros sign stealing scandal in 2017.
This was the Red Sox' first season since 2019 with fans at Fenway Park, with a limited capacity of approximately 4,500 to start the season due to the ongoing COVID-19 pandemic. The capacity was increased to approximately 9,400 for games after May 10. Fenway returned to full capacity starting May 29, with an announced attendance of 25,089 at that day's game. The first home sellout of the season was the June 25 game against the New York Yankees, with an announced attendance of 36,869.
On June 4–6, the Red Sox swept a three-game series against the rival Yankees at Yankee Stadium for the first time since June 2011. On June 13, the Toronto Blue Jays set a single-game record for home runs by a visiting team at Fenway Park, with eight. In early July, the Red Sox led MLB with five players selected to the All-Star Game. Beginning in late August, the team had a spate of positive COVID-19 testing, resulting in more than 10 players being placed on the COVID-related injured list.
The Red Sox finished the regular season with a 92–70 record and qualified for the postseason as the fourth seed in the American League (AL), defeating the fifth-seed Yankees in the AL Wild Card Game at Fenway Park on October 5. They then defeated the Tampa Bay Rays in the AL Division Series, 3–1 games. The Red Sox lost to the Houston Astros in the best-of-seven AL Championship Series in six games.
Offseason The Red Sox entered the offseason with the manager position vacant, as prior to the team's final game of the 2020 season, the team announced that Ron Roenicke would not be retained.
The Red Sox also entered the offseason with six guaranteed player contracts for 2021, totaling slightly more than $115 million: Chris Sale ($25.60 million), Xander Bogaerts ($20 million), J. D. Martinez ($19.375 million), Nathan Eovaldi ($16.88 million); Dustin Pedroia ($13.3 million), and Christian Vázquez ($4.52 million).
October On October 12, the club declined to renew the contracts for bench coach Jerry Narron and bullpen coach Craig Bjornson. On October 12, MLB announced that the Red Sox would have the fourth pick in the 2021 MLB draft, their highest pick since the 1967 MLB draft. On October 23, pitcher Domingo Tapia was claimed off of waivers by the Seattle Mariners. On October 26, the team outrighted five players to Triple-A, removing them from the 40-man roster: Zack Godley, Mike Kickham, Robinson Leyer, Tzu-Wei Lin, and Andrew Triggs. Godley, Kickham, and Triggs declined their assignments, electing to become free agents. On October 28, three more players were outrighted to Triple-A: Dylan Covey, José Peraza, and César Puello; Peraza and Puello elected free agency. On October 28, Jackie Bradley Jr. and Collin McHugh elected free agency.
November
On November 1, the team declined to exercise their $6.85 million option for Martín Pérez for the 2021 season, paying him a $500,000 buyout and making him a free agent. On November 6, Alex Cora was re-hired as the team's manager. On November 16, the team signed pitcher Kevin McCarthy to a minor-league contract. On November 17, the team signed outfielder Michael Gettys to a minor-league contract. On November 20, the deadline to protect players in advance of the Rule 5 draft scheduled for December, the team made multiple roster moves: Three players were removed from the 40-man roster: Matt Hall and Ryan Weber were designated for assignment, and the team outrighted Kyle Hart to Triple-A. Seven players were added to the 40-man roster, thus protecting them from being selected in the Rule 5 draft: Eduard Bazardo, Jay Groome, Bryan Mata, Hudson Potts, Jeisson Rosario, Connor Seabold, and Connor Wong. On November 20, changes to Cora's uniformed coaching staff were announced: Will Venable was added to the staff as bench coach and Jason Varitek was added as game planning coordinator; Kevin Walker, who had been assistant pitching coach, was named bullpen coach, and Ramón Vázquez, who as a coach had focused on statistical analysis and advanced scouting data, was named quality control coach and interpreter. On November 25, the team claimed pitcher Joel Payamps off of waivers from the Arizona Diamondbacks. In a corresponding move, pitcher Robert Stock was designated for assignment; Stock was later claimed off of waivers by the Chicago Cubs.
December On December 1, the team and Eduardo Rodríguez reached a one-year deal for the 2021 season, reportedly worth $8.3 million. On December 2, the team reached one-year deals with several players: Matt Barnes, Ryan Brasier, Austin Brice, and Kevin Plawecki. On December 3, the team traded minor-league pitcher Yoan Aybar to the Colorado Rockies for minor-league infielder Christian Koss; Aybar had not yet reached Double-A, but was on the Red Sox' 40-man roster. On December 7, Yairo Muñoz was outrighted off of the 40-man roster and assigned to Triple-A. On December 9, the team announced its 2021 Minor League Baseball affiliates; the Lowell Spinners, a Class A Short Season affiliate of the Red Sox since 1996, were dropped, as part of an MLB plan to reduce the total number of affiliated minor league teams. On December 10, the team selected pitcher Garrett Whitlock from the New York Yankees in the Rule 5 draft. On December 14, the team signed free agent outfielder Hunter Renfroe to a one-year contract. On December 23, catcher Deivy Grullón was claimed off of waivers by the Cincinnati Reds. On December 23, the team signed free agent Matt Andriese to a one-year contract.
January On January 4, the team hired Bianca Smith to serve as a minor-league coach at the team's Fenway South complex, making Smith the first African American woman to serve as a coach in a professional baseball organization. On January 4, the team signed pitcher Daniel Gossett to a minor-league contract. On January 18, the team traded minor-league infielder C. J. Chatham to the Philadelphia Phillies in exchange for a player to be named later. On January 25, the team acquired pitcher Adam Ottavino and minor-league pitcher Frank German from the New York Yankees for cash considerations or a player to be named later.
February On February 1, Dustin Pedroia announced his retirement from MLB after a 14-year career, spent entirely with the Red Sox. Knee issues had limited Pedroia to a combined nine games over the 2018 and 2019 seasons, and he missed the entire 2020 season. On February 2, the team signed utility player Enrique "Kiké" Hernández to a two-year, $14 million contract. On February 3, the team signed pitcher Garrett Richards to a one-year, $10 million contract and, in a corresponding roster move, designated pitcher Joel Payamps for assignment. Payamps was later claimed off of waivers by the Toronto Blue Jays. On February 10, the team traded Andrew Benintendi and cash considerations to the Kansas City Royals as part of a three-team trade in which Boston acquired outfielder Franchy Cordero from the Royals, minor-league pitcher Josh Winckowski from the New York Mets, and three players to be named later. On June 4, the players to be named later were identified as three prospects in the low minor leagues: outfielder Freddy Valdez from the Mets, and pitchers Grant Gambrell and Luis De La Rosa from the Royals. On February 12, the team re-signed pitcher Martín Pérez to a one-year, $4.5 million contract; in a corresponding move, pitcher Chris Mazza was designated for assignment. On February 16, the team signed free agent pitcher Hirokazu Sawamura, who previously played in Nippon Professional Baseball, to a two-year, $3 million contract; in a corresponding move, pitcher Jeffrey Springs was designated for assignment. On February 17, the team traded pitchers Chris Mazza and Jeffrey Springs to the Tampa Bay Rays in exchange for minor-league catcher Ronaldo Hernández and minor-league infielder Nick Sogard. On February 18, the team claimed pitcher John Schreiber off waivers from the Detroit Tigers. To make room on the 40-man roster, pitcher Chris Sale was placed on the 60-day injured list. On February 22, the team re-claimed Joel Payamps off waivers from Toronto. On February 24, the team signed free agent utility player Marwin González to a one-year contract; in a corresponding move, pitcher Marcus Walden was designated for assignment.
March On March 6, Joel Payamps was again claimed off of waivers by the Toronto Blue Jays. On March 7, the team signed free agent infielder Danny Santana to a minor-league contract.
Spring training "Truck Day", when the team's equipment departs Fenway Park for spring training in Florida, was February 8. Pitchers and catchers began workouts at JetBlue Park in Fort Myers on February 18; full squad workouts began on February 22.
The team had been scheduled to begin preseason games on February 26, with an exhibition against the Northeastern Huskies, but that contest was canceled. The team began Grapefruit League games on February 28, losing to the Minnesota Twins. Announcers for spring training games broadcast on NESN were Dave O'Brien and Tom Caron for play-by-play with Jerry Remy, Dennis Eckersley and Lenny DiNardo for color commentary. Boston's spring training games continued through March 30; the team compiled a 16–11 record, scoring 159 runs while allowing 131.
Regular season Major League Baseball announced the 2021 regular season schedule on July 9, 2020. The Red Sox' schedule, as originally released, spanned April 1 to October 3. The All-Star Game was scheduled for July 13. For interleague play, the Red Sox were scheduled to face National League East teams.
Opening Day lineup Originally scheduled for April 1, the team's first game of the season—at Fenway Park against the Baltimore Orioles—was postponed to April 2, due to rain.
Order No. Player Pos. 1 5 Kiké Hernández 2B 2 99 Alex Verdugo CF 3 28 J. D. Martinez DH 4 2 Xander Bogaerts SS 5 11 Rafael Devers 3B 6 10 Hunter Renfroe RF 7 12 Marwin González LF 8 7 Christian Vázquez C 9 29 Bobby Dalbec 1B — 17 Nathan Eovaldi P Source:
April April 1–April 4, vs. Baltimore Orioles
Rain caused Boston's first game to be postponed from April 1 to April 2. Nathan Eovaldi started the opener, as he had done the prior season, lasting innings while allowing one run on four hits and striking out four batters. The Red Sox were limited to two hits and two walks, taking a 3–0 loss. Baltimore also took the second game of the series, 4–2. Red Sox starter Tanner Houck held the Orioles to two runs on six hits in five innings, while striking out eight. The Orioles completed the sweep with an 11–3 win in the third game of the series. Garrett Richards took the loss in his first start for Boston, allowing six runs on seven hits in two innings. J. D. Martinez hit the Red Sox' first home run of the season. The most recent time the Red Sox had started a season 0–3 at Fenway Park was 1948, opening that season with losses to the Philadelphia Athletics.
Red Sox lost the series 0–3 (5–18 runs)
April 5–April 7, vs. Tampa Bay Rays