Boston Red Sox vs Seattle Mariners Prediction and Pick, MLB Betting Picks, 6-21-2026

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Boston Red Sox vs Seattle Mariners Prediction – 6-21-2026 – MLB Betting Picks

As a team, the Boston Red Sox are hitting 4.0 runs per match, 29th in MLB. They’ve scored 288 runs while allowing a .312 on-base percentage to their opponents. As a team, the Red Sox have 129 doubles and have launched 62 balls out of the park. They have accumulated 276 RBI’s and 601 hits this season with a club batting average of .245. Boston is slugging .383 and has been called out on strikes 604 times and walked 209 times.

They have a 2.78 strikeout to walk ratio and the pitching staff has a combined WHIP of 1.27. Red Sox pitchers have surrendered 81 home runs, and 297 runs overall (5th in league). Boston has allowed 600 base knocks (8.4 per 9 innings) and 279 earned runs. The Red Sox have a team ERA of 3.90 (8th in the league) this season and the pitching staff has struck out 612 batters. They have given up 220 walks and struck out 325 as a staff. Their FIP as a staff is 4.00.

Red Sox bullpen pitchers have come into the game with runners on 60 times and have also had 60 appearances in high leverage situations. The relief relievers have collected 35 holds on the season (19th in MLB). The Red Sox have a save percentage of 71.4% and have come into the game in 57 save situations. They’ve saved 15 of 21 opportunities throughout the campaign, but have blown 6 of those chances to preserve the game. This season the relief pitchers have inherited 89 runners and 31.5% of those runners have scored. The Red Sox have used 223 bullpen pitchers this season.

As a result, the Red Sox have converted 69.8% of the baseballs in play into outs over 5,799 innings, ranking 20th in pro baseball. At this stage of the season the Boston Red Sox had accumulated 1,933 putouts, 614 assists, and 34 errors. Their fielding percentage is presently .987, which puts them 14th in baseball, and they have turned 44 double plays.

Tolle (career 3-5) has a FIP of 3.58 versus 310 major league hitters. He’s given up 64 base hits (7.8 hits per nine innings) and walked 24. His earned run average is 3.64 (30 ER allowed) and his WHIP is 1.186. Tolle has pitched in 74 innings and has racked up 79 strikeouts over his pro baseball career.

The Seattle Mariners have a team OBP of .314 and a team batting average of.234 this season. They have been rung up 655 times (7th in the league) with 598 hits. Seattle has accumulated 97 home runs and 313 runs batted in this season. The Mariners are scoring 4.18 runs per game (20th in the league) and have a team slugging percentage of .391. They have scored 98 two-baggers, while walking 261 times and notching 322 runs.

Seattle has a team WHIP of 1.184 and is the owner of a FIP of 3.60 for the year. As a pitching staff, they are 17th in the league in hits allowed with 615. Seattle’s pitching staff has allowed 303 runs this year, but has an ERA of 3.64 (277 earned runs allowed). Their strikeout to walk ratio is 8.80 (668 strikeouts, 196 free passes). They have given up 75 home runs and they surrender 3.98 runs per 9 innings (5th in MLB).

They have a save rate of 58.1% (22nd in MLB) and have used 231 relievers out of the bullpen this season. Their bullpen pitchers have come to the mound 86 times in high leverage situations and on 58 times with base runners. The Mariners have 42 holds and 13 failed saves in 74 save opportunities. Seattle’s bullpen has gone to the mound for 31 save opportunities and come away with 18 saves. Seattle relievers have an inherited score percentage of 20.5% (78 inherited base runners).

The Seattle Mariners have turned 70 double plays and have a .987 fielding percentage (11th in professional baseball). The Mariners have 618 assists, 34 errors and 2,055 putouts on the season. The Mariners have a defensive efficiency of 69.8% (18th in professional baseball) in their 6,165 innings played.

Gilbert’s pro baseball career has seen him yield 772 hits while racking up 976 strikeouts in 921 frames. He has allowed 365 ER’s while putting up a 1.056 WHIP and a 3.5 FIP. He has a K/BB ratio of 4.86 and has faced 3,723 batters in his professional baseball career. Gilbert is 52-40 with a 3.57 earned run average and 7.5 hits allowed per nine innings.

✅ Our Boston Red Sox vs Seattle Mariners Pick: Seattle ✅

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Boston Red Sox vs Seattle Mariners Prediction and Pick, 6-21-2026, by YouWager.lv.

Boston Red Sox vs Seattle Mariners Prediction and Pick, MLB Betting Picks, 6-21-2026