2021 American League Championship Series
Team (Wins) Managers Season Houston Astros (4) Dusty Baker 95–67 (.586), GA: 5 Boston Red Sox (2) Alex Cora 92–70 (.568), GB: 8
Dates	October 15–22
MVP	Yordan Alvarez (Houston)
Umpires	David Rackley,Bill Miller (crew chief),Laz Diaz,Dan Iassogna,Jim Wolf,Alan Porter,Rob Drake
Broadcast
Television	Fox (Games 1–2) FS1 (Games 2–6)
TV announcers	Joe Buck,John Smoltz,Ken Rosenthal, andTom Verducci
Radio	ESPN
Radio announcers	Dan Shulman andEduardo Pérez
ALDS	Boston Red Sox overTampa Bay Rays (3–1) Houston Astros overChicago White Sox (3–1)
← 2020 ALCS 2022 →

The2021 American League Championship Series was the best-of-seven series inMajor League Baseball's (MLB)2021 postseason between the fourth-seededBoston Red Sox and the second-seededHouston Astros. The series determined theAmerican League pennant winner, the Astros, who advanced to the2021 World Series.

The series was played in a 2–3–2 format, with the Astros hosting the first two and game 6 (they would also have hosted game 7 if there was one) games as the higherseeded team.^[1]Fox andFS1 televised all games in the United States.

The Astros would go on to lose to theAtlanta Braves in theWorld Series in six games.

TheBoston Red Sox qualified for the postseason as the firstwild card team in the American League.^[2] They defeated theNew York Yankees in theWild Card Game,^[3] then defeated theTampa Bay Rays in four games in theDivision Series.^[4] This was Boston's 12th appearance in the American League Championship Series (ALCS), having accrued a 6–5 record in prior appearances.^[5]

TheHouston Astros qualified for the postseason as the American League West division leaders, having won the division for the fourth time in five seasons.^[6] In the American League Division Series, they defeated theChicago White Sox in four games. This was the fifth consecutive ALCS appearance for the Astros, which was the first time a team had accomplished this feat since the 1991–1999Atlanta Braves and the first in the AL since the 1971–1975Oakland Athletics.^[7] The Astros won two of their four prior ALCS appearances.^[5] When they competed in theNational League (before 2013), they won one of four appearances in theNational League Championship Series (NLCS).^[5]

This was the third playoff meeting between the Red Sox and Astros. The series was a rematch of the2018 ALCS, which was won by Boston in five games. Red Sox managerAlex Cora was the Astrosbench coach during their2017 championship season. Cora, along withgeneral managerJeff Luhnow, managerA. J. Hinch, and veteran playerCarlos Beltrán, were all suspended for a full season for their roles in theHouston Astros sign stealing scandal.^[8] After his year long suspension ended, Cora was re-hired as the Red Sox' manager on November 6, 2020.^[9] The only other postseason meeting between the Astros and Red Sox came during the2017 American League Division Series, which was won by Houston in four games.

The Astros won the season series with the Red Sox, 5–2.^[10] The seven games between the two clubs were played over the course of ten days (May 31 through June 9) and the Astros outscored the Red Sox by 17 runs.^[11]

The Astros' ace starting pitcherLance McCullers Jr. was left off the ALCS roster due to a forearm injury.^[12]

Houston won the series, 4–2.

Framber Valdez of the Astros was matched up againstChris Sale of the Red Sox, but the game would soon turn into a bullpen affair. The Red Soxloaded the bases with two outs in the top of the first, but were unable to score. The Astros scored a run in the bottom of the first;Jose Altuve, who had drawn a leadoff walk, scored on asacrifice fly byYordan Alvarez. In the bottom of the second, Houston loaded the bases with one out but did not score. A leadoff home run byKiké Hernández in the top of the third tied the game.^[13] A one-out walk byXander Bogaerts, followed by a single and anerror, gave Boston a 2–1 lead, andHunter Renfroe then doubled to make it a 3–1 game. With two out in the top of the third,Yimi García relieved Houston starterFramber Valdez. In the bottom of the frame, Sale left with two on and two out, relieved byAdam Ottavino. The game stayed this way for the next few innings as both teams would use seven relievers. A two-run homer by Altuve off ofTanner Houck with two out in the bottom of the sixth tied the game, 3–3. It was the 20th postseason homer of Altuve's career, tying him withDerek Jeter for third on the MLB all-time list while also marking him as the fastest hitter to 20 home runs in the postseason.^[14]Carlos Correa put Houston ahead, 4–3, with a solo home run in the bottom of the seventh off ofHansel Robles. After the Astros loaded the bases with none out in the bottom of the eighth off of Red Sox relieverHirokazu Sawamura, an Altuve sacrifice fly gave Houston a 5–3 lead. Boston got a run back to start the ninth, as Hernández homered off of HoustoncloserRyan Pressly. Pressly then retired the next three batters, giving Houston the win and a 1–0 lead in the series.^[15][16]

The teams combined to use 16 total pitchers in the game, eight each. Hernández went 4-for-5 with two home runs while falling a triple short of thecycle. It gave him 29total bases in his four most recent postseason games, tying the mark for the most total bases in a four-game span in postseason history withReggie Jackson.^[17]

Boston hadgrand slams byJ. D. Martinez (left) andRafael Devers in Game 2.

Boston tied the series at one game each, with a 9–5 win in Game 2. Starting pitchers wereNathan Eovaldi for Boston, andLuis García for Houston.J. D. Martinez hit agrand slam in the top of the first to give Boston a 4–0 lead over the Astros. It was the firstpostseason grand slam in the first inning by a Red Sox player sinceJ. D. Drew in2007 ALCS Game 6.^[18] García left early in the top of the second due to knee discomfort.^[19]Rafael Devers hit a second grand slam in the top of the second, making the Red Sox the first team in postseason history to hit two grand slams in one game.^[20] A fourth-inning homer byKiké Hernández, his third of the series, made it 9–0. The Astros rallied with two outs in the bottom of the fourth for three runs, trimming Boston's lead to 9–3.Yuli Gurriel andJason Castro each hit solo home runs in the bottom of the ninth, making it 9–5, the final score.^[21]

The teams combined to use 10 total pitchers in the game, five each. Hernández was 2-for-4 with a home run and a single, setting a new Major League record for the mosttotal bases in a five-game playoff span, with 34; it also set a new Red Sox franchise record for the most total bases inany five-game span.^[22]

Boston won Game 3, 12–3, to take a 2–1 lead in the series.Eduardo Rodríguez started for Boston andJosé Urquidy started for Houston. The Red Sox sent 11 men to the plate in the bottom of the second, scoring six runs. Four of the runs came on agrand slam byKyle Schwarber, the third by a Red Sox batter in two games. Urquidy left with two outs in the second, having allowed six runs (five earned) on five hits and two walks while striking out one batter. Boston added three runs in the bottom of the third, including a two-run homer byChristian Arroyo, extending the Red Sox' lead to 9–0. Astros right fielderKyle Tucker hit a three-run homer with two out in the top of the fourth, making it a 9–3 game. Boston made it 11–3 in the bottom of the sixth via a two-run homer byJ. D. Martinez.Hansel Robles relieved Rodríguez in the top of the seventh, Rodríguez having allowed three runs on five hits and no walks while striking out seven.Rafael Devers hit a solo home run in the bottom of the eighth, extending the lead to 12–3, the final score.^[23]

The Astros used six pitchers, while the Red Sox used four. Boston's three grand slams—two in Game 2 and one in Game 3—was the first time a major league team hit three slams in any postseason series.^[24]

Nick Pivetta started for Boston andZack Greinke started for Houston. The Astros took an early 1–0 lead via a solo home run byAlex Bregman with two outs in the top of the first. In the bottom of the first,Rafael Devers walked with two outs, thenXander Bogaerts homered to give the Red Sox a 2–1 lead. Greinke left with one out in the bottom of the second, having allowed two runs on one hit and three walks; he did not strike out a batter.Christian Arroyo hit a one-out triple in the bottom of the fourth, but the Red Sox were unable to score him. Bogaerts hit a one-out double in the bottom of the fifth and was also left stranded. Pivetta left after the fifth inning, having allowed one run on two hits and two walks; he struck out three.Jose Altuve tied the game, 2–2, with a home run off ofGarrett Whitlock to lead off the eighth inning.Nate Eovaldi came in to pitch the top of the ninth, andCarlos Correa led off with a double overHunter Renfroe in right field. With two outs and after a controversial non-strike three call by home plate umpireLaz Díaz,Jason Castro singled to drive in Correa and give the Astros a 3–2 lead. Houston was able toload the bases, and Boston brought inMartín Pérez.Michael Brantley hit his first pitch for a double that scored three runs, giving Houston a 6–2 lead. A single byYordan Alvarez plated another run, making it 7–2. Correa, batting for the second time in the inning, hit a ball fielded by Pérez that was thrown away for anerror, allowing another run to score, and a single byKyle Tucker drove in the Astros' seventh and final run of the inning, which was the most scored in a postseason inning in Astros history. It was also the first time a team had scored seven runs in the 9th inning (or later) in a postseason game since2007 and sixth time overall.^[25][26] HoustoncloserRyan Pressly came in to pitch the bottom of the ninth; he allowed two singles, but prevented Boston from scoring as Houston evened the series, 2–2.^[27]

Altuve's home run was the 21st of his postseason career, which moved him to third on the all-time list and set the record for most career postseason home runs by an infielder, breaking the tie withDerek Jeter.^[28]

Earlier on the day of the game, anMD-87 jet carrying 18 Astros fans and three crew members crashed nearHouston Executive Airport as they were departing for the game; there were no significant injuries reported.^[29][30]

Chris Sale started for the Red Sox andFramber Valdez started for the Astros. Houston took a 1–0 lead on a solo home run byYordan Alvarez in the top of the second inning, to the opposite field over theGreen Monster.^[31] Valdez did not allow a Boston baserunner until the fifth inning. The Astros scored five runs in the top of the sixth, chasing Sale with one out. Houston's runs came on four hits, a walk, and anerror, giving the Astros a 6–0 lead. The teams traded runs in the seventh, making it 7–1. Boston's only run of the game was a solo homer byRafael Devers. Houston added two more runs in the top of the ninth, for the 9–1 final. Both Alvarez andYuli Gurriel had three hits and three RBIs.^[32] All of Alvarez' hits landed to the opposite field, marking the first occasion in Alvarez' career in which he collected at least three opposite-field hits.^[33] Sale took the loss, having pitched5+1⁄3 innings while allowing four runs (two earned) on three hits and two walks while striking out seven batters. Valdez went eight innings and got the win, limiting Boston to one run on three hits and a walk while striking out five.^[32] He became the seventh visiting pitcher to go at least eight innings while allowing one run or fewer atFenway Park in the postseason, and the first sinceCharles Nagy in the1998 ALDS.^[34] The Astros took a 3–2 lead in the series, the third ALCS in a row to go at least six games.^[35]

Luis García started for Houston andNathan Eovaldi for Boston, a rematch of Game 2. The Astros took a 1–0 lead in the bottom of the first; with two outs,Alex Bregman singled then was driven in on a double byYordan Alvarez that hit off the glove of Red Sox center fielderKiké Hernández. In the bottom of the fourth, Houston had runners on second and third with no outs, but Eovaldi struck out the next two batters,intentionally walkedYuli Gurriel, and then struck outChas McCormick to end the threat. Eovaldi left with one out in the bottom of the fifth, having allowed one run on five hits while striking out four; he was relieved byJosh Taylor. García held the Red Sox hitless through five innings; he left in the top of the sixth after allowing a two-out triple to Hernández.^[36] Hisno-hit bid of5+2⁄3 innings before allowing a hit was the second most by a rookie pitcher in postseason history.^[37] García was relieved byPhil Maton, who ended the threat by gettingRafael Devers to pop out. Alvarez opened the bottom of the sixth with a triple off of Taylor near the right-field line. AfterCarlos Correa washit by a pitch fromTanner Houck,Kyle Tucker grounded into a double play, scoring Alvarez and giving Houston a 2–0 lead. In the top of the seventh, Boston had runners at first and third with one out;Kendall Graveman struck outTravis Shaw and catcherMartín Maldonado threw outAlex Verdugo, who had been running on the pitch, at second base to end the inning. Alvarez collected his fourth hit of the game in the bottom of the eighth, singling to give the Astros runners at first and second with one out. After Correa grounded out, Tucker homered off ofAdam Ottavino, extending Houston's lead to 5–0. AstroscloserRyan Pressly entered to pitch the top of the ninth. He retired the side in order, as Houston advanced to theWorld Series.^[38]

With the win, 72-year-oldDusty Baker became the oldest manager to win an American League pennant, while being the second-oldest manager to reach the World Series afterJack McKeon in2003.^[39] After the game, Alvarez was named theALCS MVP, having batted 12-for-23 (.522) in the series.^[40] Seven of his hits came in the last two games; he out-hit the entire Red Sox team in those games, which was the first time in postseason history a player had done so in the final two games of a series.^[41] The Red Sox, having scored 27 runs in the first 28 innings of the Series, then scored only one run in the last 26 innings.

2021 ALCS(4–2):Houston Astros beatBoston Red Sox

• 2021 National League Championship Series

• Browne, Ian; McTaggart, Brian (October 12, 2021)."Red Sox-Astros Game 1 FAQ".MLB.com. RetrievedOctober 13, 2021.
• Roche, Conor (October 23, 2021)."Cora, Red Sox hitters explained what went wrong in the final three games of the ALCS".Boston.com. RetrievedOctober 23, 2021.
• "Interference in Boston? Laz Diaz's Astros-Red Sox No-Call".closecallsports.com. October 20, 2021. RetrievedOctober 23, 2021.

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