MLB Baseball: Arizona Diamondbacks vs. Seattle Mariners Preview, Prediction & Odds - Sept. 11, 2021

by Chuck Sommers

Friday, Sep 10, 2021
Game time: 9:10 p.m. ET
Venue: T-Mobile Park, Seattle, WA
Where to watch: Bally Sports Arizona, ROOTNW

Opening Odds at USA Sportsbooks


DraftKings: Mariners -160, Diamondbacks +140
BetMGM: NL
Caesars: NL

Season record (entering Friday)
Diamondbacks: 45-95 (Last place, NL West)
Mariners: 76-64 (3rd place, AL West)

Larry Ness is caught in a 3-day MLB slump (just 2-6) but this 38-year vet has not slumped very often. He's gone 159-116, +$27,417 with all plays since May 15 (4-month span) and checks in having earned a profit of $23,690 (at $100/unit) since Opening Day. His 3-game Friday card is highlighted by this 10* Division Game of the Month. Catch Larry’s and other plays available right now at the Shop Picks page, where you can find all of the Best Bets from our champion sports handicappers.

Diamondbacks - Mariners preview and analysis


Recent form
Diamondbacks: Lost 5 straight
Mariners: 7-3 in last 10

Do the Seattle Mariners have one more run left in them?

We’ll find out this weekend at home against the Arizona Diamondbacks with Game  2 of this three-game series on Saturday at T-Mobile Park in Seattle.

The Mariners enter Friday sitting 5.5 games back of the Houston Astros for first place in the American League West and two games back of the New York Yankees for the second wild card spot in the AL.

Seattle had a five-game winning streak end this week against said Astros, who took two of three in a three-game set over Seattle. This was after the Mariner just won two of three in Seattle to closen the gap. Now with the Oakland Athletics also tied with the Mariners in the standings, we’ve reached the tight ship in September baseball. Seattle has seven at home, including a massive three-game series against the Boston Red Sox, and then nine on the road with Kansas City (three), Oakland (four) and the Los Angeles Angels (three).

Not to mention three more each at home against the A’s and Angels, so there’s still a lot of baseball to be played for the Mariners.

But Seattle’s offense has picked it up a notch since making this run. During its five-game winning streak, Seattle outscored opponents 29-14. Even if three of those wins came against these same D-Backs, the Mariners have bats that are capable of being dangerous threats these final three weeks.

The Mariners will send ace Chris Flexen to the mound to face the Diamondbacks for the second time in less than a week. Flexen, the right-hander, was solid last time out (6 IP, 3 ER, 4 K, 2 BB), but something about getting back at home and leading this pitching staff to what would be the start of a last-ditch effort to a playoff run.

Humberto Castellanos will take the mound for the Diamondbacks, who enter Friday losers of five in a row and 10 of 11. Castellanos, the 23-year-old from Mexico, is 1-1 with a 3.65 ERA and 1.30 WHIP in three starts and seven appearances. He’ll follow Madison Bumgarner, who gets the start on Friday.

Prediction


The Diamondbacks have scored a total of 35 runs in those 10 losses in 11 games, while scoring eight in that lone victory. That clip of 3.5 runs per game isn’t going to get it done for the Arizona batters. This seems like a perfect time for Flexen to, er, flex his muscles and get the Mariners a win on Saturday. Mariners win 7-1.

Betting trends


The Diamondbacks, who are 17-52 on the road entering Friday, are 17-50 (-18.9 net games on the moneyline) when an underdog of +150 or more.

The Mariners are 9-9 (-4.5 net games) when favored between -125 to -175. 

Players to watch


Diamondbacks: Top hitter Josh Rojas has swung the bat well during Arizona’s 10-15 stretch over the last 25 games. Rojas is batting .289 and has driven in 13 runs.

Mariners: Infielder Ty France continues to be one of the MVPs of this Seattle team. Since Aug. 18, which Seattle has gone 12-8, France is batting .329 with four homers and eight RBI.

Projected lineup


Diamondbacks:
Nick Ahmed (R) SS
Ketel Marte (S) CF
Carson Kelly (R) C
Christian Walker (R) DH
Pavin Smith (L) 1B
Andrew Young (R) 2B
Josh Rojas (L) 3B
Henry Ramos (S) LF
Jake McCarthy (L) RF

Mariners:
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

Probable starting pitchers: Humberto Castellanos (ARI) vs. Chris Flexen (SEA)

Statistical leaders


Diamondbacks:
Batting average: Pavin Smith (.270)
Hits: Pavin Smith (122)
Home runs: Josh Rojas (11)
RBI: David Peralta (55)
Stolen bases: Josh Rojas (7)
Wins: Merrill Kelly (7)
Saves: Tyler Clippard (5)
ERA: Merrill Kelly (4.30)

Mariners:
Batting average: Ty France (.291)
Hits: Ty France (143)
Home runs: Kyle Seager (34)
RBI: Kyle Seager (94)
Stolen bases:
Wins: Chris Flexen (11)
Saves: Kendall Graveman (10)
ERA: Chris Flexen (3.56)

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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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