Arizona Diamondbacks vs Boston Red Sox Picks and Prediction for Tuesday August 18, 2026

The Arizona Diamondbacks visit the Boston Red Sox on Tuesday night at Fenway Park in Boston, Massachusetts. First pitch is scheduled for 7:10 p.m. ET on August 18, with MLB.TV providing coverage. Arizona enters at 66-59 overall and 30-32 on the road, while Boston is 66-58 overall and 29-31 at home. The Diamondbacks have won two of their last five games, while the Red Sox are also 2-3 over their last five. ESPN's matchup predictor gives Boston a 64.7% chance of winning compared with 35.3% for Arizona. At the time of this writing the odds were not released. Check out our free MLB picks for more baseball predictions and betting analysis.

Starting Pitchers

Merrill Kelly gets the start for Arizona with an 8-10 record, 5.11 ERA, and 1.48 WHIP through 125 innings. The right-hander has allowed 132 hits and 25 home runs while striking out 82 and walking 53. Boston counters with Ranger Suarez, who enters at 4-3 with a 3.25 ERA and 1.19 WHIP through 108 innings. The left-hander has surrendered 97 hits and only six home runs while recording 110 strikeouts against 31 walks. Suarez holds substantial advantages in ERA, WHIP, strikeouts, walks, and home runs allowed, giving Boston the stronger starting pitching profile.

Arizona Brings the Slightly Stronger Run Production

Arizona enters Tuesday at 66-59 overall but sits slightly below .500 away from home at 30-32. The Diamondbacks are 2-3 over their last five games. Both victories came on the road by scores of 10-3 and 2-0, but they followed those wins with a 5-3 defeat in their most recent contest.

The Diamondbacks are batting .244 with 567 runs, 1,023 hits, and 124 home runs. Arizona owns a .316 on-base percentage and .399 slugging percentage. The pitching staff has posted a 4.09 ERA and 1.27 WHIP while opponents are batting .250.

Arizona's offensive production is one of its better arguments entering this matchup. The Diamondbacks have scored 18 more runs than Boston despite the teams having identical home-run totals. However, most of the other offensive numbers are extremely close, leaving Arizona with little margin for error given its disadvantage on the mound.

Boston Holds the Pitching Advantage

Boston enters Tuesday at 66-58 overall and 29-31 at Fenway Park. The Red Sox are 2-3 over their last five games and are coming off an 8-3 defeat. Their two recent victories were impressive from a pitching standpoint, with Boston recording shutouts by scores of 4-0 and 7-0.

The Red Sox are hitting .248 with 549 runs, 1,026 hits, and 124 home runs. Boston has a .320 on-base percentage and .400 slugging percentage. Its pitching staff has been the bigger statistical advantage, carrying a 3.52 ERA and 1.22 WHIP while limiting opposing hitters to a .240 batting average.

Boston has small advantages in batting average, on-base percentage, and slugging percentage, but pitching creates the more meaningful separation. The Red Sox hold a 0.57-run advantage in team ERA and have allowed fewer baserunners. Combined with the favorable scheduled starting matchup, Boston has the stronger overall statistical setup Tuesday night.

Arizona Diamondbacks vs Boston Red Sox Picks and Prediction

Pick: Boston Red Sox Moneyline

Boston is the moneyline selection. The offensive numbers are close enough that neither team holds a decisive advantage at the plate, but the pitching comparison favors the Red Sox. Boston owns a 3.52 team ERA and 1.22 WHIP compared with Arizona at 4.09 and 1.27. The scheduled starting matchup strengthens that advantage considerably, making the Red Sox the preferred side if the eventual moneyline remains reasonable.

Pick: Under 9.0

Take the under if the total is set at 9.0. Boston has recorded two shutouts over its last four games, and its scheduled starter enters with a 3.25 ERA and 1.19 WHIP. Arizona's pitching creates some concern, particularly after allowing six or more runs in two of its last five games, but neither offense has been particularly dominant on a season-long basis. With Boston holding the stronger pitching profile, Under 9.0 is the preferred total.

Disclaimer: This preview was completed before play on Monday.