The Mariners’ biggest problem has taken a turn for the worse

The Seattle Mariners are no longer leading the AL West, nor are they even above .500 after dropping their third straight series.

Seattle Mariners acquire infielder Buddy Kennedy from Giants

The main problem is easy to point to: the Mariners haven’t been scoring enough runs. When they scored a fourth run on Sunday in Cleveland, it snapped a streak of 13 straight games where they scored three runs or less, tying the longest such streak in team history.

As for why Seattle hasn’t been scoring runs, you can point to a slugging ability that has lagged in 2026. As Luke Arkins of the Mariners Consigliere newsletter pointed out Monday, the M’s slugging has declined from last year more than all but two other teams. For the full 2025 regular season, the Mariners were 10th in MLB with a .420 slugging mark and third with 238 home runs. In 2026, they’re 27th in slugging at .382 and 11th in home runs with 102.

The real trouble is that it’s a problem that looked to get better, only to rear its head even worse in the last two weeks.

The Mariners’ obvious problem as they scuffled to a 25-29 start is that they weren’t hitting the ball with much authority, which is something the lineup is built to do with Julio Rodríguez, Josh Naylor, Luke Raley, Dominic Canzone, Rob Refsnyder and especially Cal Raleigh all on the roster.

Through May 24, the M’s ranked 23rd in MLB with a .375 slugging mark, though they were able to be just above league-average with a .101 wRC+ and had a respectable 8.5% barrel rate that was 12th in baseball (see a breakdown of the Mariners’ slugging numbers through three different stretches this season at the bottom of this post).

Then on May 25, the Mariners’ offense got going with an eight-game win streak that kicked off a 12-5 stretch and surged Seattle into first place in the division. Over those 17 games from May 25 through June 12, the Mariners were second in MLB in both slugging (.478) and home runs (33), as well as third with a 128 wRC+ and 10th with an 8.7% barrel rate.

But in 16 games since June 13, the Mariners’ offense has skidded even worse than before while the team has fallen out of first place. In Seattle’s current 5-11 stretch, it is last in MLB with a .285 slugging mark, just nine home runs and a 4.9% barrel rate.

What’s wrong?

It’s hard to find a concrete answer for why the Mariners’ slugging problems have been so pervasive this season, but one thing that’s a likely factor at least recently is that their lineup has dealt with numerous minor injuries this month.

Sunday: Mariners’ Raley out of lineup with sore elbow

Every regular position player except for second baseman Cole Young has missed at least a little time in June for an injury concern, and that’s the sort of thing that can have an impact upon a player’s return whether it’s due to the issue lingering or the break from playing time throwing off their timing at the plate.

Regardless of the reason, the Mariners need to find a way to get their offense on track now that they’re chasing the Texas Rangers for the division lead rather than the other way around.

Seattle Mariners’ slugging this season

• March 26-May 24 (25-29 record)

.375 slugging (23rd), 60 home runs (tied 10th) 101 wRC+, .271 BABIP (26th), 8.5% barrel rate (12th), 39.8% hard hit rate (15th), 31.6% squared-up contract rate (23rd), 23.4% squared-up swing rate (27th)

• May 25-June 12 (12-5 record)

.478 slugging (second), 33 home runs (second), 128 wRC+ (third), .299 BABIP (16th), 8.7% barrel rate (10th), 39.1% hard hit rate (15th), 31.5% squared-up contact rate (19th), 24.2% squared-up swing rate (20th)

• June 13-28 (5-11 record)

.285 slugging (last), nine home runs (last), 69 wRC+ (29th), .252 BABIP (29th), 35.1% hard hit rate (23rd), 4.9% barrel rate (last), 34.6% squared-up contact rate (fifth), 26.4% squared-up swing rate (seventh)

Mariners news and more

• Morosi: Mariners’ slumping offense needs stars to step up
• Prospect Felnin Celesten adds the cycle breakout season
• Seattle Mariners don’t lose veteran utility man after DFA

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