2021 ALCS Predictions | Red Sox vs Astros Best Bets & Projections

Last Updated: Oct 19, 2021

After two exciting American League Division Series’ (ALDS), the American League Championship Series (ALCS) begins on Friday night. The Houston Astros will be hosting the Boston Red Sox to start the 2021 ALCS.

Boston made the postseason as a Wild Card team, and they were able to advance to the ALCS by beating the New York Yankees in the Wild Card game and the Tampa Bay Rays in the ALDS.

During the ALDS, the Red Sox beat the Rays as a +160 series underdog in a bet that my model recommended. Additionally, I correctly recommended the Red Sox to win the ALDS 3-1 at +450 odds.

Houston made the postseason as the AL West champion, and they won the ALDS against the Chicago White Sox in only four games. As a result of their strong performance during the regular season and ALDS, the Astros are heavy favorites to win the ALCS.

To figure out the best ALCS bets, I came up with win probabilities for each team in each game based on lineups and starting pitching matchups.

Below, I go over my model’s probabilities in all potential ALCS games, and then I go over what the prices should be on ALCS futures.

Sportsbook Play of the Day

Before making your next ALCS futures bet, you should know that Caesars Sportsbook is one of the best around. Take advantage of Caesars’ outstanding welcome bonus, which gives you a second-chance bet of up to $5,000 when you use our promo code .

Read Chris Wassel’s Caesars Sportsbook review for more insight and get your welcome bonus below, or continue reading this analysis for our best Red Sox vs. Astros bet picks.

Red Sox vs. Astros ALCS Game Projections

Game 1: Boston at Houston

Chris Sale (5-1, 3.16 ERA) vs. Framber Valdez (11-6, 3.14 ERA)

Kevin Davis Model Projection: Astros 50.8%

Game 1 Pick: Red Sox if +112 or better, Astros if +105 or better

Game 2: Boston at Houston

Nathan Eovaldi (11-9, 3.75 ERA) vs. Luis Garcia (11-8, 3.30 ERA)

Kevin Davis Model Projection: Red Sox 50.2%

Game 2 Pick: Red Sox if +108 or better, Astros if +109 or better

Game 3: Houston at Boston

Jose Urquidy (8-3, 3.62 ERA) vs. Eduardo Rodriguez (13-8, 4.74 ERA)

Kevin Davis Model Projection: Red Sox 57.7%

Game 3 Pick: Astros if +148 or better, Red Sox if -125 or better

Game 4: Houston at Boston

Zack Greinke (11-6, 4.16 ERA) vs. Nick Pivetta (9-8, 4.53 ERA)

Kevin Davis Model Projection: Red Sox 57.5%

Game 4 Pick: Astros if +150 or better, Red Sox if -123 or better

Game 5: Houston at Boston

Luis Garcia (11-8, 3.30 ERA) vs. Nathan Eovaldi (11-9, 3.75 ERA)

Kevin Davis Model Projection: Red Sox 56.3%

Game 5 Pick: Astros if +136 or better, Red Sox if -116 or better

Game 6: Boston at Houston (If Necessary)

Eduardo Rodriguez (13-8, 4.74 ERA) vs. Jose Urquidy (8-3, 3.62 ERA)

Kevin Davis Model Projection: Astros 50.7%

Game 6 Pick: Red Sox if +112 or better, Astros if +105 or better

Game 7: Boston at Houston (If Necessary)

Chris Sale (5-1, 3.16 ERA) vs. Lance McCullers Jr. (13-5, 3.16 ERA)

Kevin Davis Model Projection: Astros 53.1%

Game 7 Pick: Red Sox if +121 or better, Astros if -104 or better

Jose Altuve and Carlos Correa, Houston Astros

For the second year in a row, the Houston Astros return to the Championship Series to take on the Boston Red Sox in the 2021 ALCS. (Image: USA TODAY Sports)

Pitching Preview

Not to be captain obvious, but the single biggest factor that will determine the series winner will be how both teams use their starting pitching. Additionally, pitching is also the most predictable factor in who wins the ALCS.

During the regular season, teams typically rely on a starting rotation of five starting pitchers (basically every team other than the Tampa Bay Rays). During the postseason, teams usually rely on a four-man rotation.

What makes both the Astros and Red Sox unusual this year is that in the ALDS, both teams had a three-pitcher starting rotation.

In the ALDS, Boston relied on Eduardo Rodriguez as the starter for Games 1 & 4, Chris Sale in Game 2, and Nathan Eovaldi in Game 3.

Chris Sale is the best starting pitcher in the Red Sox rotation, but he is coming off a serious injury that caused him to miss the end of the 2019 season, the entire 2020 season, and most of this year.

During the regular season, Sale put up respectable numbers but averaged fewer than five innings per start. In Game 2, the Rays feasted on Sale as he lasted only one full inning and allowed five earned runs.

If Sale can pitch well in Game 1, chances are the Red Sox will rely on him for both Game 4 and a potential Game 7 in Houston.

With Tanner Houck and Nick Pivetta in the bullpen this postseason, the Red Sox are likely to continue relying on them as long relievers. As a result, I believe that Boston can sustain a three-man rotation for the ALCS.

Houston’s weakness as a team this postseason is their starting rotation. Their one bright spot is Lance McCullers Jr., who had solid performances in both Games 1 and 4 of the ALDS. However, McCullers got injured in Game 4 against the White Sox, and he is likely to miss the ALCS.

As a result, my model conservatively projects McCullers to pitch only in a potential Game 7 in Houston.

Lineup Preview

While Houston has a weakness with their starting rotation in comparison to the Red Sox, they have the best lineup in MLB this season. The Astros hitters averaged 5.39 runs per game this season, which was the best out of all 30 teams.

With 2B Jose Altuve, 3B Alex Bregman, DH Yordan Alvarez, SS Carlos Correa, and OF’s Michael Brantley and Kyle Tucker, it is very hard for pitchers to pitch around the Astros lineup. Last year, Houston’s strong offensive core almost beat the Tampa Bay rays in the ALCS.

While the Red Sox lineup is not as good as the Astros, it is a strong lineup. During the regular season, Boston averaged 5.16 runs per game, which was the 4th best in MLB.

Led by DH J.D. Martinez and a slew of other strong hitters, the Astros’ depleted rotation is going to have a tough task in quieting Boston’s bats.

Red Sox vs. Astros ALCS Futures Bets

Red Sox vs. Astros ALCS Winner Bets

Best Bet: Boston Red Sox ALCS Series Winner (+135) at Caesars (would bet up to +110)

Wager: 2 Units

It is not a surprise to me that my model’s projections and the betting odds are far off for the ALCS. Usually, it’s a bad thing when your model is off from the odds, but based on my model’s accuracy during the regular and postseason, I trust my numbers.

In the ALDS, my model viewed it as a tossup between the Red Sox and the Rays, and as a result, I went ham on the Red Sox. Based on what I value in Boston’s pitching staff and their lineup, it shouldn’t be a surprise that I originally viewed the ALCS as close to a tossup.

What tipped the scales in favor of the Red Sox are reports that Lance McCullers Jr. is likely to miss the ALCS due to injury.

While it is plausible that Houston’s lineup can carry this team, their path to the World Series is more difficult with Framber Valdez, Luis Garcia, Jose Urquidy, and potentially Zach Greinke starting.

Personally, I am not betting on the series winner as I already have Red Sox World Series and Pennant tickets from the beginning of the postseason, but if I didn’t have any outstanding futures, I would lay a large wager on them winning the ALCS.

Kevin Davis Series Winner Model Projection: Red Sox 55.2%

Red Sox vs. Astros ALCS Exact Score Bets

Best Bet: Boston Red Sox 4-1 Series Winner (+800) at Caesars (would bet up to +650)

Wager: 0.5 Units

Best Bet: Boston Red Sox 4-0 Series Winner (+1800) at Caesars (would bet up to +1500)

Wager: 0.25 Units

Without boring you with the math, let me explain how my model calculated the odds of each exact series score.

To figure out the chances of each exact series score, I simulated each potential ALCS game 100,000 times. After my simulations in Microsoft Excel, I counted the number of times that each series ended in a specific score.

Unsurprisingly, the only exact score markets I like involve the Red Sox winning the ALCS since they are my preferred pick (betting-wise, not in terms of rooting interest since I am a Yankees fan).

The Series Exact Score props that my model likes the most are for Boston to win 4-0 or 4-1 as each involves Chris Sale pitching two games, and no Lance McCullers Jr.

Thanks for reading our Red Sox vs. Astros ALDS Predictions! For more MLB betting tips, check out our 2021 World Series Champion Predictions.


Kevin Davis

Kevin Davis is a Betting Analyst at The Game Day residing in Hoboken, NJ. Previously a Bronx resident, Kevin got his start betting on sports at his local Bronx barbershop. When sports betting was legalized across the river in Jersey, Kevin was there on the ground floor making regular trips to the Hoboken PATH station or for soup dumplings in Fort Lee. Previously, Kevin has written for The Action Network, and Vegas Insider.

Related articles


Get $1,500 in Bonus Bets

5 stars

Bet $5, Get $150 in Bonus Bets or First Bet Safety Net

5 stars

Bet $10, Get $200 in Bonus Bets

5 stars

Get A Bonus Bet Up to $1,000

5 stars

Bet $5, Get $200 in Bonus Bets

5 stars

Get Up To $250 Second Chance Bonus Bet

5 stars

If you or someone you know has a gambling problem and wants help, please call 1-800-GAMBLER.

21+ and present in OH. Gambling Problem? Call or text 1-800-GAMBLER (CO, DC, IL, IN, LA, MD, MS, NJ, OH, PA, TN, VA, WV, WY).

Call 877-8-HOPENY or text HOPENY (467369) (NY).

Please Gamble Responsibly. Call 1-800-NEXT-STEP (AZ), 1-800-522-4700 (KS, NV), 1-800-327-5050 (MA), 1-800-BETS-OFF (IA), 1-800-270-7117 for confidential help (MI).

All betting content on TheGameDay.com is exclusively intended for audience members 21 years and older who are permitted to gamble in legal states. The Game Day may earn revenue from site visitor referrals to betting services.

Responsible Gaming: Many sportsbooks offer ways to encourage responsible gaming, including the establishment of limits to deposits, spending, and time dedicated to betting.

The Game Day is a TGD Marketing Ltd. endeavor.