Seattle Mariners vs Arizona Diamondbacks Pick – 6/9/2025

On June 9, 2025, the Arizona Diamondbacks will host the Seattle Mariners at Chase Field for the first game of an interleague series. The Diamondbacks currently sit at 31-34, struggling this season, while the Mariners are slightly better at 33-31, showcasing an above-average performance.

Arizona's Merrill Kelly, the #58 ranked starting pitcher in MLB according to advanced stats, has been solid this season with a 6-2 record and a commendable ERA of 3.43. However, his xERA of 4.03 suggests he might be due for a slight regression. He projects to pitch 5.6 innings today, allowing 2.6 earned runs. The D-Backs offense has been a bright spot, ranking 4th in MLB, with a potent lineup that has excelled in home runs and batting average.

In contrast, Seattle’s Emerson Hancock has struggled significantly, holding a 2-2 record with an ERA of 5.19. His performance suggests he's one of the weaker pitchers in the league, and projections indicate he may allow 3 earned runs over 5 innings today. The Mariners' offense, while ranking 6th in home runs, has been inconsistent, sitting at 21st in batting average.

Despite the Mariners being the underdog, the Diamondbacks’ strong offensive capabilities and Kelly's reliable pitching present a favorable matchup. With the D-Backs favored at -165, their high implied team total of 5.27 runs indicates confidence in their ability to capitalize on Hancock's weaknesses. It shapes up to be an intriguing contest as Arizona seeks to build momentum against Seattle.

Quick Takes Seattle Mariners:

Emerson Hancock's 2424-rpm fastball spin rate this year ranks in the 83rd percentile out of all SPs.

• Spin rate is a key component to fastball success in generating strikeouts and preventing runs.

Cal Raleigh has seen a big increase in his exit velocity on flyballs this year; just compare his 97.8-mph average to last year's 94.9-mph EV.

• Most home runs are flyballs, and the harder those flyballs are hit, the more often they turn into home runs. This is a strong indicator of power.

Cal Raleigh pulls many of his flyballs (43.3% — 100th percentile) and will have to hit them out towards the league's 3rd-deepest RF fences today.

• This player's skill set does not match up particularly well with the park he's in today, which may lead to worse-than-usual performance.

Quick Takes Arizona Diamondbacks:

Given that groundball pitchers are least effective against flyball hitters, Merrill Kelly (42.8% GB% per the leading projection system, THE BAT) will be a bit disadvantaged in today's game with 2 FB hitters in Seattle's projected offense.

• This mostly has to do with the way the hitter's swing plane interacts with the pitch trajectory, and it can create diminished performance across all categories and hidden value few are considering.

Extreme flyball hitters like Eugenio Suarez usually hit worse against extreme flyball pitchers like Emerson Hancock.

• This mostly has to do with the way the hitter's swing plane interacts with the pitch trajectory, and it can create diminished performance across all categories and hidden value few are considering.

The Arizona Diamondbacks have been the 4th-luckiest offense in the majors this year, according to the leading projection system (THE BAT X), and are likely to hit worse the rest of the season

• When teams overperform their projected talent level, markets may overvalue them even while they are likely to perform worse in the near future.

Game Trends

• The Arizona Diamondbacks have hit the 1st Five Innings (F5) Moneyline in 24 of their last 44 games (+11.80 Units / 19% ROI)
• The Seattle Mariners have hit the Game Total Under in 10 of their last 15 away games (+5.60 Units / 34% ROI)
• Leody Taveras has hit the Hits Under in 7 of his last 9 games (+6.35 Units / 69% ROI)

Seattle Mariners vs Arizona Diamondbacks Prediction

Predicted Final Score: Seattle Mariners 4.68, Arizona Diamondbacks 5.18

• Date: June 9, 2025
• Venue: Chase Field
• Starting Pitchers:
  • Emerson Hancock - Mariners
  • Merrill Kelly - D-Backs

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