Chicago Cubs vs Seattle Mariners Picks and Prediction for Friday August 21, 2026

The Chicago Cubs visit the Seattle Mariners at T-Mobile Park in Seattle, Washington, on Friday, August 21, 2026. First pitch is scheduled for 10:10 PM ET, with coverage on MLB.TV. Chicago enters the matchup at 74-54 overall and 36-27 on the road, while Seattle is 60-67 overall and 33-29 at home. At the time of this writing the odds were not released.

Chicago remains in the National League Central race despite dropping three of its last five games, while Seattle has won three of its last five and comes home after a road trip. Readers looking for more analysis can also check out our free MLB picks.

Starting Pitchers

Matthew Boyd is expected to start for Chicago and enters at 8-2 with a 4.02 ERA and 1.24 WHIP across 85.0 innings. He has allowed 79 hits, struck out 68, walked 26, and surrendered 13 home runs. Seattle is scheduled to counter with Emerson Hancock, who is 7-7 with a 3.30 ERA and 1.11 WHIP over 128.0 innings. Hancock has allowed 110 hits while recording 119 strikeouts, 32 walks, and 16 home runs allowed.

Cubs Looking to Regain Momentum

Chicago comes into this game at 74-54 overall and 36-27 away from home. The Cubs have gone 2-3 over their last five, most recently losing 3-0 to the White Sox after winning the previous two games of that series. They also dropped two games to St. Louis before that.

The Cubs have posted a .248 team batting average with 656 runs, 1,089 hits, and 164 home runs. Their .337 on-base percentage and .418 slugging percentage are both stronger than Seattle's corresponding numbers. On the pitching side, Chicago owns a 4.14 ERA and 1.26 WHIP while allowing opponents to hit .245.

Chicago's biggest advantage is offensive production. The Cubs have scored 160 more runs than Seattle and also hold substantial advantages in batting average, on-base percentage, and slugging percentage. The concern is that their offense was shut out in the most recent game, but over the full season they have been the considerably more productive lineup.

Mariners Lean on Pitching

Seattle enters at 60-67 overall and 33-29 at home. The Mariners are 3-2 over their last five games, including a 7-5 win over Milwaukee in their most recent contest. Their recent stretch also includes wins over Houston by scores of 3-2 and 10-5.

The Mariners are batting .230 as a team with 496 runs, 966 hits, and 145 home runs. They own a .310 on-base percentage and .377 slugging percentage. Seattle's pitching staff has been more effective, carrying a 3.97 ERA and 1.22 WHIP while holding opposing hitters to a .247 average.

Seattle's clearest strength in this matchup is run prevention. The Mariners have the lower team ERA and WHIP, and Hancock enters with better season numbers than Boyd in both categories. Seattle will likely need that pitching edge because its offense has been much less productive than Chicago's over the course of the season.

Chicago Cubs vs Seattle Mariners Picks and Prediction

Pick: Chicago Cubs Moneyline

Chicago gets the slight edge because its offensive profile is meaningfully stronger, and that matters in a matchup where both starting pitchers have been reasonably steady. The Cubs have scored 656 runs compared with Seattle's 496, and Chicago also owns the better batting average, on-base percentage, and slugging percentage.

Seattle has the pitching advantage on paper with Hancock, but the gap is not large enough to outweigh Chicago's season-long offensive edge. The Cubs are also 36-27 on the road, showing they have been capable away from home. Take the Chicago Cubs on the moneyline.

Pick: Under 8.5

If the total is set at 8.5, the under is the preferred play. Hancock enters with a 3.30 ERA and 1.11 WHIP, while Boyd has allowed fewer than one hit per inning over 85 innings. Seattle's offense has also produced only 496 runs this season, which lowers the likelihood of a high-scoring game.

Chicago has the better lineup, but Seattle's home setting and stronger overall pitching numbers give this matchup a lower-scoring profile. Take the Under if the total is set at 8.5.

This preview was completed before play on Thursday.