George Kirby’s Rough Mariners Stretch Shows His Contact Problem Is Catching Up

Kirby’s command-first style is starting to come with a cost.

Jun 3, 2026; Seattle, Washington, USA; Seattle Mariners starting pitcher George Kirby (68) pitches to the New York Mets during the first inning at T-Mobile Park. Mandatory Credit: Steven Bisig-Imagn Images | Steven Bisig-Imagn Images

George Kirby’s 2026 season has been odd from the very beginning. It’s been known that he’s drawing more contact than he has in recent seasons. But it’s fair to wonder if it’s all starting to catch up to him. 

Kirby has gone 0-3 with a 7.28 ERA, a 1.62 WHIP and 30 hits allowed over his last four starts. It looks like hitters are seeing him well, they know his sequences, and punishing him for it.

His latest outing against the New York Mets made the issue hard to ignore. Kirby took the loss in Seattle’s 7-1 defeat, his final line: 4 IP, 9 H, 5 R, 4 ER, 1 BB, 5 K on 89 pitches, 55 for strikes.

That line almost tells the whole story by itself. Kirby didn’t issue a lot of walks, no surprise. He stayed in the zone and challenged batters. Defensive lapses aside, Kirby was hittable.

Bo brings home ✌️ pic.twitter.com/vzxzrJARSI

— New York Mets (@Mets) June 3, 2026

George Kirby’s Command Only Works When Hitters Still Have to Miss

With Kirby, his greatest strength can turn against him when the shape of his arsenal isn’t sharp enough. He lives in the zone. He loves to attack and dare hitters to beat him before he beats himself. Usually, that’s why he’s been so good over the years. And the Mariners have built so much trust in Kirby because his starts are often very clean.

Lately, that same formula has started to look dangerous. And with Kirby, maybe more than any other Mariners starter, we knew this kind of stretch was always possible. 

The fastball still is fine. His four-seamer is averaging 96.6 mph. His sweeper looks like a solid weapon as well with a .219 expected batting average, .294 expected slugging percentage and .242 expected wOBA against it.

The problem is the rest of the mix has given hitters too many comfortable looks. The sinker has not missed many bats. The knuckle curve is wildly alarming, with hitters batting .462 and slugging .615 against it. Even though the expected numbers are kinder than the actual damage, the pitch is not finishing hitters the way it did before as its whiff rate has cratered to 16.9 percent after sitting at 39.2 percent in 2025.

A command-first starter needs to throw strikes. So it’s hard to tap into what exactly needs to change for Kirby. It’s probably as simple as having hitters respect more than just two offerings. A hitter can sit dead red on his fastball because they know he’s going to throw it. If they are not worried about the knuckle curve finishing them or the sinker running off barrels, the at-bat gets a lot simpler. Regardless of the count, hitters know the same thing: Kirby hates walks, and he’s going to make them swing the bat.

Right now, the Mariners are watching too many plate appearances turn into easy contact.

Kirby entered this cold run with a 5-2 record and a 2.82 ERA. Four starts later, his ERA has climbed to 4.04. 

There is no need to overreact yet. Kirby has earned more patience than that. But they also cannot treat it like nothing.

Kirby has made real adjustments this season. He has moved away from the splitter, added a cutter and slightly reshaped the way his arsenal looks. He’s also no longer holding the split grip in the initial setup phase, and his arm angle has climbed from 29 degrees to 33. For most pitchers, that might sound like nothing. For Kirby, his whole game is built on precision, deception and repeatability. Small changes can create big tells.