Seattle Mariners vs Boston Red Sox Picks and Prediction for Tuesday September 1 2026

The Seattle Mariners visit the Boston Red Sox at Fenway Park in Boston, Massachusetts, on Tuesday, September 1. First pitch is scheduled for 6:45 PM ET, with MLB.TV providing coverage. Seattle enters at 64-73 overall and 27-42 on the road, while Boston is 74-63 overall and 34-32 at home. The Mariners have lost four straight and sit five games back in the American League West, while Boston has dropped two straight and sits third in the American League East. Boston leads the season series 2-1, and ESPN Analytics gives the Red Sox a 69.2% chance to win compared with 30.8% for Seattle. At the time of this writing the odds were not released. Check out our free MLB picks for more baseball predictions throughout the season.

Starting Pitchers

Bryan Woo is scheduled to start for Seattle and enters at 9-9 with a 4.36 ERA and 1.10 WHIP across 142.1 innings. He has allowed 126 hits while recording 142 strikeouts against only 30 walks and has surrendered 17 home runs. Sonny Gray is scheduled for Boston and brings an impressive 16-4 record with a 2.82 ERA and 1.18 WHIP through 143.2 innings. He has allowed 132 hits while striking out 128 against 37 walks and has surrendered 15 home runs. Seattle's starter has displayed excellent control, but Boston owns the clear advantage in ERA and overall results from its scheduled starter.

Mariners Searching for an Offensive Spark

Seattle enters Tuesday at 64-73 and has fallen five games behind the American League West leader. The Mariners have lost four straight and are just 1-4 over their last five games. They were swept in a three-game road series against Toronto, losing 8-1, 4-3 and 7-0 after splitting their final two listed games against Philadelphia. Seattle has scored only eight runs across those five contests and has been shut out twice during that stretch.

The Mariners are batting .227 with 530 runs, 1,024 hits and 157 home runs this season. They carry a .307 on-base percentage and .372 slugging percentage. Those numbers trail Boston in batting average, runs, hits, on-base percentage and slugging percentage, leaving Seattle with a significant offensive disadvantage entering this matchup.

Seattle's pitching has been more competitive, producing a 4.16 team ERA and 1.24 WHIP while holding opponents to a .249 batting average. The Mariners have recorded 1,157 strikeouts against only 359 walks. Their pitching gives them a chance to remain competitive, but the offense must improve considerably after being held to three runs or fewer in four consecutive games.

Red Sox Look to Rebound at Fenway

Boston enters the matchup at 74-63 overall and remains above .500 despite a difficult recent stretch. The Red Sox are only 1-4 over their last five games and return home after losing 16-1 and 9-2 in their final two listed contests against New York. Boston has been shut out twice during its last five games as well, so neither offense enters Tuesday producing consistently strong results.

The Red Sox are batting .249 with 609 runs, 1,142 hits and 138 home runs. Boston owns a .323 on-base percentage and .403 slugging percentage. Although Seattle has hit more home runs, Boston has scored 79 more runs while producing 118 more hits, and the Red Sox hold substantial advantages in batting average, on-base percentage and slugging percentage.

Boston has also posted the stronger overall pitching numbers with a 3.57 ERA and 1.23 WHIP while limiting opponents to a .241 batting average. The Red Sox have 1,168 strikeouts against 394 walks. Combined with the advantage in Tuesday's scheduled starting pitching matchup and a 34-32 home record, Boston has several statistical edges despite its recent two-game skid.

Seattle Mariners vs Boston Red Sox Picks and Prediction

Pick: Boston Red Sox Moneyline

The Boston Red Sox Moneyline is the side to back in this matchup. Both teams enter struggling, but Boston has the better overall record, the stronger offense and the better team ERA. The Red Sox also have a significant advantage with their scheduled starter carrying a 16-4 record and 2.82 ERA compared with Seattle's scheduled starter at 9-9 with a 4.36 ERA. Seattle's current offensive slump is particularly concerning, with the Mariners scoring just eight total runs over their last five games while being shut out twice. Boston leads the season series 2-1, and the overall statistical profile supports the home team. Take the Boston Red Sox Moneyline.

Pick: Under 8.5

The Under 8.5 is my preferred total if that number becomes available. Seattle has scored three runs or fewer in four consecutive games and has been shut out twice in its last four. Boston's offense has also struggled recently, scoring nine total runs over its last five games and being shut out twice. The scheduled starters have combined for only 67 walks across 286 innings, while Boston carries a 3.57 team ERA. Seattle's 4.16 ERA is respectable enough to keep this from automatically becoming a high-scoring matchup. Take the Under if the total is set at 8.5.

Final Picks: Boston Red Sox Moneyline and Under 8.5

This preview was completed before play on Monday. Starting pitchers, betting lines and other game information are subject to change before the game begins.