MLB Baseball: Boston Red Sox vs. Seattle Mariners Preview, Prediction & Odds -- Sept. 13, 2021

by Chuck Sommers

Game time: 10:10 p.m. ET
Venue: T-Mobile Park, Seattle, WA
Where to watch: NESN, ROOTNW

Opening Odds at USA Sportsbooks

DraftKings: Red Sox -130, Mariners +110
Caesars: NL

Season record (entering Sunday)
Red Sox: 81-64 (2nd place, AL East
Mariners: 77-65 (2nd place, AL West)

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Red Sox - Mariners preview and analysis

Recent form
Red Sox: 4-6 in last 10
Mariners: 7-3 in last 10

Just like that, the Boston Red Sox are in trouble.

After the Red Sox lost in walk-off fashion Sunday to the Chicago White Sox, Boston now finds itself in legitimate range of falling out of the playoff race by the end of the night.

As for the Seattle Mariners, well … it could be better.

The Red Sox and Mariners will begin a crucial three-game series in Seattle with playoff baseball implications up for grabs and some serious problems for the loser.

Boston lost 2-1 on Sunday, and the series, to the White Sox despite a strong 5.1 IP effort from starter Nick Pivetta (5 strikeouts, 0 ER, 0 BB. As a result, the Toronto Blue Jays are now the top wild-card team in the American League after winning three of four against the Baltimore Orioles this weekend. This is your daily reminder that the Blue Jays put up 44 runs in three games on the Orioles.

Back to your regularly-scheduled programming. The Red Sox and Mariners offense both faltered this weekend in underwhelming performances. Seattle failed to get anything going against the underdog Arizona Diamondbacks, while Boston’s bats fizzled with only four combined runs in the two losses in Chicago.

The Mariners, at time of publishing, are 2.5 games out of the wild card race despite an uninspired showing against the last-place Diamondbacks. Safe to say that the loser of this series will find themselves farther away from the postseason chase with two and a half weeks remaining in the regular season.

Eduardo Rodriguez is expected to start on the mound for the Red Sox, while the Mariners will go to starting pitcher Logan Gilbert for the series opener. Both pitchers have an ERA of over 5.00 but have proven to be solid pieces in the rotation for both teams.


Although the Mariners fell asleep at the wheel this weekend, the inconsistent Boston offense reared its ugly head on the road once again. And given how this weekend had to be a wakeup call for Seattle after only winning on Friday, and still trailing the Houston Astros by a handful of games, expect Seattle to put up a much better effort than on Saturday and Sunday and get a much-needed victory on Monday.

Betting trends

The Red Sox are 49-35 (-2.4 ner games on the moneyline) when favored by -110 or higher this season.

The Mariners are 36-27 (+18 net games) when the moneyline is between +100 and +150.

Players to watch

Red Sox: Boston needs to start getting production from its offensive MVP, Rafael Devers. He has only one home run in his last 13 games, to go with six RBI, and is batting just .244 in that stretch. They’re not catching the Tampa Bay Rays, but if Boston wants to make something out of this season, they’ll need it from Devers.

Mariners: Seattle’s Mitch Haniger hit a home run in back-to-back games, and it seems at times he’s the most consistently offensive player the Mariners have. He has a hit in nine of his last 10 games and has six RBI in that span. He’s going to need to continue that run if the Mariners want to hold off the Oakland Athletics.

Projected lineup

Red Sox:
Enrique Hernandez (R) CF
Kyle Schwarber (L) DH
Hunter Renfroe (R) RF
Xander Bogaerts (R) SS
Rafael Devers (L) 3B
Bobby Dalbec (R) 1B
Christian Vazquez (R) C
Danny Santana (S) LF
Jose Iglesias (R) 2B

J.P. Crawford (L) SS
Mitch Haniger (R) RF
Kyle Seager (L) 3B
Ty France (R) 1B
Abraham Toro (S) 2B
Luis Torrens (R) DH
Jarred Kelenic (L) CF
Tom Murphy (R) C
Jose Marmolejos (L) LF

Statistical leaders

Red Sox:
Batting average: Xander Bogaerts (.301)
Hits: J.D. Martinez (146)
Home runs: Rafael Devers (33)
RBI: Rafael Devers (101)
Stolen bases: Christian Vazquez (8)
Wins: Eduardo Rodriguez (11)
Saves: Matt Barnes (24)
ERA: Nathan Eovaldi (3.57)

Batting average: Ty France (.289)
Hits: Ty France (144)
Home runs: Kyle Seager (34)
RBI: Kyle Seager (94)
Stolen bases: Dylan Moore (20)
Wins: Chris Flexen (11)
Saves: Kendall Graveman (10)
ERA: Chris Flexen (3.73)

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Chuck Sommers

About the Author:

Chuck Sommers has camped outside of sportsbooks since he can remember, learning the tricks and nuances of the trade. He still has nightmares of betting $5,000 on the Raiders in the Tuck Rule game but has since turned that to 25 years of veteran handicapping greatness. You can find him mostly in the shadows at the Red Rock or Aliante casinos wondering if the over is cashing on any given Sunday.

All photographic images used for editorial content have been licensed from the Associated Press.

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