Seattle Mariners vs Arizona Diamondbacks Prediction 6/9/25 MLB Picks

The Seattle Mariners are visiting the Arizona Diamondbacks on Monday, June 9th at the Chase Field in the opening game of this series. We will look at this from a betting perspective and determine the best bets for this game. Here’s a Seattle Mariners vs Arizona Diamondbacks Prediction. We will examine:

The Arizona Diamondbacks’ recent form and player performance

The Seattle Mariners’ recent form and player performance

Recent betting trends and streaks involving the Arizona Diamondbacks

Recent betting trends and streaks involving the Seattle Mariners

Recent betting trends in games played between the Seattle Mariners vs Arizona Diamondbacks

A summary that ties it all together and produces a favorable betting outcome for the Seattle Mariners vs Arizona Diamondbacks game

Arizona Diamondbacks Preview

The Arizona Diamondbacks have a 31-34 record this season and are sitting in 4th place in the NL West. The Diamondbacks have a 15-17 home record and are 29-31 in over/under. They are coming off a 2-4 road defeat by the Reds and have three consecutive losses. Over is 6-4 in their last 10 games, and they are playing the Padres and the Blue Jays next.

The Diamondbacks have a .252 batting average this season, a .330 OBP, and a .442 slugging percentage. Arizona’s pitching staff has a 4.86 ERA and 1.34 WHIP. Josh Naylor leads the Diamondbacks with 68 hits, and he is the team’s best hitter with a .283 batting average. Eugenio Suarez leads the team in RBI, with 48, and in home runs, with 18.

Merrill Kelly (R) will take the mound for the Diamondbacks, and he has a 6-2 record, 3.43 ERA, and 0.99 WHIP. He has been better at home, with a 3.03 ERA across six home starts, and he finally bounced back after two straight bad starts with a shutout against the Braves in 7 innings pitched. In his only previous start against the Mariners back in 2023, he gave up 3 runs across 5 innings of work.

Seattle Mariners Preview

The Seattle Mariners have a 33-31 record this season and are sitting in second place in the AL West. The Mariners have a 17-14 road record and 33-27 in over/under. They are coming off a 3-2 road victory over the Angels, which ended their previous five-game losing streak. Under is 4-1-1 in their last 6 games, and they are playing the Red Sox and the Guardians next.

The Mariners have a .239 batting average this season, a .319 OBP, and a .394 Slugging percentage. Seattle’s pitching staff has a 3.91 ERA and 1.31 WHIP. Julio Rodriguez leads the Mariners in hits with 64, while Cal Raleigh leads the team both in RBI with 53 and in home runs with 26. J.P. Crawford is the team’s best hitter with a .280 batting average.

Emerson Hancock (R) will take the mound for the Mariners, and he has a 2-2 record, 5.19 ERA, and 1.47 WHIP. He has been better at home with a 3.25 ERA across five road starts, and he has been playing much better lately, having given up 2 runs or less in three of his last four starts. This will be his first career start against the D-backs.

Why the Arizona Diamondbacks will win

• The Mariners have lost each of their last six night games after playing the previous day.
• The Diamondbacks have won each of their last four home games against AL West opponents.
• The Mariners have failed to cover the run line in each of their last six games following a win.
• The Diamondbacks have covered the run line in each of their last four games as favorites against AL West opponents.
• The Diamondbacks have led after 3 innings in each of their last four games against AL West opponents.
• The Diamondbacks have won the first inning in three of their last four games against American League opponents.
• The Diamondbacks have led after 5 innings in seven of their last eight home games against American League opponents.

Why the Seattle Mariners will win

• The Mariners have won each of their last nine night games against NL West opponents that held a losing record.
• The Diamondbacks have lost seven of their last eight games as favorites.
• The underdogs have covered the run line in each of the Mariners’ last 11 games.
• The Diamondbacks have failed to cover the run line in seven of their last eight games as favorites.
• The Mariners have led after 3 innings in five of their last six games against the Diamondbacks.
• The Mariners have won the first inning in three of their last four road games.
• The Mariners have led after 5 innings in each of their last four games against the Diamondbacks.

Total Runs Facts

• Each of the last six games between the Mariners and Diamondbacks have gone UNDER the total runs line.
• Seven of the Mariners’ last eight games as underdogs have gone UNDER the total runs line.
• The ‘Inning 1 OVER 0.5 runs’ market has hit in seven of the Diamondbacks’ last eight games against American League opponents.
• The ‘Inning 1 OVER 0.5 runs’ market has hit in six of the Mariners’ last seven night games at Chase Field.

Matchup/League Facts

• The Diamondbacks rank 2nd in the league for doubles this season (122).
• The Diamondbacks rank 28th in the league for runs allowed this season (341).
• The Mariners rank 29th in the league for doubles this season (80).
• The Mariners are one of only three teams in the league to rank top 10 in both steals and home runs this season.

Seattle Mariners vs Arizona Diamondbacks Prediction

The Mariners are 3-1 in their last 4 meetings against the Dbacks, and 3-1 in their last 4 visits to Arizona. Their last six overall meetings have gone under the total.  

In this Seattle Mariners vs Arizona Diamondbacks Prediction, the Diamondbacks are coming as -165 home favorites. This is a spot where the Dbacks are clearly overvalued, as they have a worse overall record than the Mariners; they also have fewer wins at home than the Mariners have on the road. The Dbacks also have the 4th-worst bullpen in the league, but Kelly’s expected ERA is 4.06, and Hancock has been playing good for the Mariners lately.

Both teams are in poor form lately, and the Dbacks should not be such big favorites, which gives great value to the underdog. I will take a chance with the Seattle Mariners to win at plus money in this one.