(Re)setting expectations for the Mariners offense

The Mariners lineup looks the same and entirely new.

(Editor’s note: We are delighted to welcome Ryan Blake to the Lookout Landing staff! You may well know him from years within the LL community, from various realms of the internet as Leaky Barn, as well as his writing at his site Swings and Takes. Please give him a warm welcome, or perhaps for many of us simply a re-introduction!)

The Seattle Mariners offense is barreling towards the top of the leaderboards in what will likely be the best month of the Dipoto era.

Seattle’s xwOBA sits at .354 after another strong performance Sunday. They spent the last week jockeying with Aaron Judge (and whoever else the Yankees employ) for the league’s best mark. It’s not only the Mariners best April xwOBA of the Statcast era, but it’s trending to be their best xwOBA split for any month, nudging out the .352 mark set in August 2023. There are still two games left this month.

The ‘x’ in xwOBA stands for “expected.” The metric is an estimate of wOBA if results on batted balls were replaced with quality of contact — i.e., it doesn’t count in the box score. The Mariners of August 2023 (and of many other months, frankly) produced more “actual” value. But given April’s cooler temperatures tend to deflate offense across MLB, and that the Mariners play half their games in the uber-suppressive T-Mobile Park, xwOBA provides a crucial glimpse into the quality of the lineup so far. And hypothetical value aside, the Mariners have the fourth best “real” wOBA (.334) and the seventh most runs (138). Their team wRC+, which adjusts for the park and the league’s run environment, ranks second (125).

Stretches in baseball don’t necessarily adhere to the Gregorian calendar. The following chart shows the Mariners rolling xwOBA in the post “retool” era. Each point represents the previous 1,000 plate appearances. By this view, the Mariners current run is not quite as exceptional as late 2023, but what we’re seeing now is impressive nonetheless.

One of the subplots of the 2025 season is the new coaching staff. I like this chart because it makes clear the previous staff wasn’t necessarily holding back the Mariners lineup, as Scott Servais and Jarret DeHart proved capable of stewarding a good offense and an elite stretch. But I also don’t think it’s pure coincidence the Mariners outlook improved after the change in leadership. For whatever reason, last year’s group, which is now this year’s group, didn’t respond to the 2024 iteration of Control The Zone. If you believe coaches offer specific wisdom and batters listen, then it’s possible this group benefited from the right voice(s) at the right time.

What changed?

The 2024 Mariners whiffed and whiffed and whiffed some more. They spent most of the season chasing the strikeout record. But it wasn’t all bad. They swung hard, and when they connected, good things happened. They finished the season in the top 10 by a variety of quality of contact metrics, even if the whiffs limited their total output.

What’s interesting is the whiffs remain in 2025. The Mariners 28.7% whiff rate is the second worst in MLB behind only Colorado, and more than half their at bats have progressed to two strikes. But the Mariners strikeout rate this year is roughly middle of the pack at 23.4%, down significantly from the record-setting pace of 28.7% last April. It’s a trend that began soon after the new coaching staff took over.

One thing Edgar and Kevin Seitzer emphasized in interviews over the last several months is the old school wisdom of “battling” with two strikes — get the ball in play up-the-middle-the-other-way. Batters are given the latitude to do what they will before two strikes, but once the strikeout looms, it becomes the team’s at bat. We actually see this in the data. The Mariners whiff rate in two-strike counts (25.2%) is actually six points lower than their whiff rate in non-two-strike counts (31.0%), a bigger positive gap than any club in baseball. Because of this, their xwOBA with two strikes is 35 points higher than it was last year. They’re taking big hacks at pitches early, and when the situation demands it, they “scratch and claw and fight” to provide something more than nothing.

The tradeoff? Well, there isn’t one so far. The Mariners quality of contact is better than ever. Their .415 xwOBAcon is second in MLB. They also rank second in barrels per batted ball and fourth in barrels per plate appearance. Their .625 xwOBA on fly balls and line drives not only leads the league but would be the second best mark for any team ever (if it held for another 134 games — it remains early). Notably, Seitzer’s Braves of yesteryear flank the 2025 Mariners for best air balls and can be found throughout the top 10.

Whatever the Mariners are doing at the plate, they are getting balls in play, in the air, and with authority, and now without as many rally-killing K’s. Perhaps this helps explain why the Mariners lead MLB in walks despite an elevated chase rate — no team has seen fewer pitches in the zone so far, as opposing pitchers attempt to avoid the punishment within.

This outburst isn’t too-too surprising. The Mariners are a good team. They’ve had a top 10 offense the last few years, and they were projected to be a top 10 offense again this year. I’m not sure they will be The Best Offense In Baseball come October, but their 125 wRC+ since the leadership change is the best in MLB, in a sample approaching a half season. It’s working for now.