Seattle Mariners vs Chicago White Sox Prediction 5/9/2026 Today’s MLB Picks

The Seattle Mariners and the Chicago White Sox meet Saturday in MLB action from Rate Field. We will look at this from a betting perspective and determine the best bets for this game. Here’s a Seattle Mariners vs. Chicago White Sox prediction.

Starting Pitching Matchup

The Seattle Mariners will send out Luis Castillo for the start here and Castillo is 0-3 with a 6.29 ERA and 31 strikeouts this season. In his career, Castillo is 2-0 with a 1.71 ERA and 28 strikeouts against the White Sox. Chicago will start Anthony Kay here and Kay is 1-1 with a 5.70 ERA and 20 strikeouts this season. This will be Kay’s first career start against the Mariners.

Seattle Mariners Recap

The Seattle Mariners come into this game looking to add on to their 12-8 win over Chicago from Friday’s series opener to sit at 19-20 this season. After this series, the Mariners will head on the road for a series against the Astros.

Mariners Win Back-To-Back Games

Entering Friday, Luke Raley has 6 home runs and 16 RBIs this season. Cole Young’s added 37 hits with 6 doubles, a triple, 3 home runs and 20 RBIs and Cal Raleigh has 24 hits with 4 doubles, 7 home runs and 18 RBIs as well this season. Randy Arozarena has 36 hits with 9 doubles, 3 home runs and 12 RBIs as well on the year. Josh Naylor also has 32 hits with 4 home runs and 17 RBIs as well on the year. Julio Rodriguez has also added 39 hits with 7 doubles, 5 home runs and 17 RBIs.

Chicago White Sox Recap

The Chicago White Sox come into this game looking to bounce back from their loss at the hands of Seattle on Friday to sit at 17-21 on the year. After this series, the White Sox will take on the Kansas City Royals at home.

White Sox Drop 3 In A Row

Going into Friday’s matchup, Munetaka Murakami has 31 hits with 14 home runs and 28 RBIs while Miguel Vargas has 28 hits with 4 doubles, a triple, 7 home runs and 18 RBIs and Colson Montgomery has 30 hits with 7 doubles, 9 home runs and 23 RBIs. Luisangel Acuna has 14 hits and Tristan Peters has 21 hits with a double so far this season. Chase Meidroth also has 37 hits with 7 doubles, 2 home runs and 5 RBIs this year.

Seattle Mariners @ the Chicago White Sox Betting Trends: May 9, 2026

• Probable Starting Pitcher: Anthony Kay      Record this season: 1-1      ERA: 5.70
• Home Record: 0-0
• Last 5 against Mariners: 0-0

Why the Chicago White Sox will win

• The White Sox have won each of their last five games as underdogs against AL West opponents following a home loss.
• The Mariners have lost five of their last six games as favorites against American League opponents following a road win.
• The underdogs have covered the run line in 13 of the White Sox’s last 14 games.
• The Mariners have failed to cover the run line in nine of their last 10 night games following a win.
• The Mariners have trailed after 5 innings in seven of their last eight games as road favorites against American League opponents.
• The White Sox have led after 3 innings in seven of their last eight games as underdogs against American League opponents.

• Probable Starting Pitcher: Luis Castillo      Record this season: 0-3      ERA: 6.29
• Road Record: 0-2
• Last 5 against White Sox: 2-0

Why the Seattle Mariners will win

• The Mariners have won nine of their last 10 games against the White Sox.
• The White Sox have lost eight of their last nine games against the Mariners following a loss.
• The White Sox have failed to cover the run line in each of their last seven home games following a loss.
• The road team has covered the run line in eight of the Mariners’ last nine games.
• The Mariners have led after 5 innings in each of their last four games against the White Sox.

Total Runs Facts

• Each of the White Sox’s last four night games after playing the previous day have gone UNDER the total runs line.
• Five of the Mariners’ last six road games against AL Central opponents have gone OVER the total runs line.
• The ‘Inning 1 OVER 0.5 runs’ market has hit in seven of the White Sox’s last eight night games against AL West opponents.
• The ‘Inning 1 UNDER 0.5 runs’ market has hit in six of the Mariners’ last seven road games against AL Central opponents.

Chicago White Sox Player Prop Facts

• Miguel Vargas has recorded at least one hit in each of the White Sox’s last 11 games as underdogs.
• Austin Hays has hit a home run in two of his last three appearances against the Mariners.
• Munetaka Murakami ranks T1st in the league in Home Runs (15) this season.

Seattle Mariners Player Prop Facts

• Julio Rodriguez has hit a home run in three of the Mariners’ last four road games against the White Sox.
• Luis Castillo has recorded six or more strikeouts in three of his four previous appearances against the White Sox.
• Julio Rodriguez has recorded at least one hit in each of the Mariners’ last 12 Saturday games.
• Randy Arozarena ranks T9th in the league in Steals (9) this season.

Matchup/League Facts

• The White Sox rank 30th in the league for doubles this season (41).
• The White Sox rank 27th in the league for hits this season (290).
• The Mariners rank 1st in the league for walks allowed this season (96).
• The Mariners rank T27th in the league for doubles this season (51).

Seattle Mariners vs. Chicago White Sox Prediction

I’m on the White Sox in this one. Castillo’s had some solid career numbers against Chicago, but he’s still be on a downturn for much of the season and is truly hard to get behind in his current form. I think that the White Sox still have a potent lineup and while Kay isn’t my favorite option in Chicago’s rotation, I think he can be serviceable enough to help Chicago get the W here. Give me the White Sox.

Chris Ruffolo's Pick: Chicago White Sox +120