St. Louis Cardinals vs Seattle Mariners Prediction, 9/8/2025 MLB Picks, Best Bets & Odds

Game: St. Louis Cardinals vs Seattle Mariners

Date: Monday, September 8, 2025

Location: T-Mobile Park in Seattle, WA

TV: Root Sports Northwest

Odds/Point Spread: St. Louis (+110) Seattle (-132)

T-Mobile Park is the site where the Seattle Mariners (73-67) will compete against the St. Louis Cardinals (70-71) on Monday. The moneyline on this game has St. Louis at +110 and Seattle is priced at -132. The total has been set at 8.5. The expected starting pitchers will be Miles Mikolas and Bryan Woo.

As a team, the St. Louis Cardinals are knocking in 4.4 runs per game, which has them sitting at 17th in the league. They have earned 613 runs and have an OBP of .315. The Cardinals have accumulated 229 doubles as a unit and have hit 135 baseballs out of the park. They have 584 runs batted in as well as 1,166 hits on the campaign, and their average at the plate sits at .247. St. Louis has a slugging percentage of .384 and have been called out on strikes 1,121 times, while drawing a walk on 421 occasions.

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The Cardinals hold a team earned run average of 4.27 for the season (20th in MLB), and the staff has struck out 1,041 batters. Cardinals pitchers have conceded 146 long balls in addition to 649 runs in total (22nd in the league). Their pitching staff has walked 394 opposing batters and their FIP sits at 4.04 as a team this season. St. Louis has given up 1,239 hits (9.0 per 9 innings) in addition to 591 earned runs. Their K/BB ratio is 2.64 and the pitching staff has a team WHIP of 1.31.

The Cardinals relief pitchers have a save percentage of 66.1% and have entered the game in 139 save situations. The bullpen pitchers have inherited 185 runners for the year and 33.0% of those runners earned a run for their team. Cardinals pitchers have gone to the mound with runners on 134 times in addition to having 132 appearances in high leverage situations. The Cardinals have sent 414 relief pitchers to the hill this year. The relief pitchers have racked up 80 holds for the year (12th in MLB). They have compiled 37 saves over the course of the season and have blown 19 of their 56 chances to get a save.

The St. Louis Cardinals have 3,737 putouts this season, as well as 1,353 assists and 69 errors. Their fielding rate is holding steady at .987 which puts them in 13th in pro baseball, and they have turned 109 double plays. The Cardinals have turned 69.1% of balls hit into play into outs out of their 11,211 innings on the field, which has them ranked 22nd in pro baseball.

Mikolas has taken the hill for 1,232 innings and has earned 881 K's during his pro baseball career. His earned run average is 4.24 (580 earned runs allowed) and he has a WHIP of 1.217. He has allowed 1,257 hits (9.2 hits per nine innings) and has 242 walks. Mikolas (71-74 career win-loss record) holds a FIP of 4.17 while he has gone up against 5,135 batters in the major leagues.

The Seattle Mariners have compiled an on-base percentage of .317 in addition to a batting average of .241 this season. They have struck out on 1,245 occasions (4th in the league) and have accounted for 1,145 hits. Seattle has accumulated 200 HRs over the course of the season as well as 613 RBIs. The Mariners have a team slugging percentage of .410 and they are recording 4.56 runs per contest (12th in the league). They have tallied 188 two-baggers, while taking a walk 468 times and putting up 638 runs.

The Mariners have a WHIP of 1.264 with a FIP of 4.13 as a team for the year. Their K/BB ratio is 8.50 (1,193 strikeouts against 416 bases on balls). They come in at 21st in the league as a pitching staff in total hits surrendered with 1,176. They have conceded 169 home runs and they relinquish 4.48 runs per 9 innings (18th in MLB). The Seattle pitching staff have surrendered 627 runs on the year while having an ERA of 4.05 (566 earned runs relinquished).

Sitting with 135 save situations, the Mariners have earned 77 holds in addition to 22 blown saves. Seattle has called on bullpen pitchers to step onto the hill in 58 save opportunities and they have earned 36 saves. Their relievers have stepped onto the mound 188 times in high leverage situations in addition to 114 occasions with base runners. Seattle relievers have an inherited score percentage of 25.2% out of 127 inherited runners. They are ranked 19th in MLB holding a save rate of 62.1%, and they have dispatched 470 relief pitchers to the hill so far this season.

In 11,337 innings played, the Mariners are sitting with a defensive efficiency of 70.1% (12th in baseball). The Seattle Mariners have gotten 103 double plays and own a fielding percentage of .988 (7th in baseball). The Mariners have accrued 1,177 assists, 59 errors and have accumulated 3,779 putouts on the season.

In his MLB career, Woo has surrendered 301 base hits while he has earned 363 strikeouts in 378 innings pitched. Woo (25-15 career win-loss mark) has a 3.26 earned run average and has given up 7.2 hits per 9 innings. He has given up 137 ER's while holding a WHIP of 1.002 and a FIP of 3.2. He has a strikeout to walk ratio of 4.65 and he has faced 1,514 opposing hitters so far in his career.

Who will win tonight's MLB game against the spread or moneyline?

Tony Sink's Pick: Take St. Louis (+110)

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