SEATTLE — Left-hander Ryan Weathers is set to make his Yankees debut Monday night against the Seattle Mariners at T-Mobile Park. It is the first real test of a pitching experiment the Yankees have been building since they acquired the 26-year-old from the Miami Marlins in January for four minor leaguers, including three of the organization’s Top 30 prospects.
The New York Yankees have not lost a game in 2026. Their pitching staff has allowed one run in 27 innings. And now, the most intriguing arm in their rotation is about to take the mound for the first time in pinstripes.
His father, former big league reliever David Weathers, is expected to be in the stands. But the younger Weathers will not be pitching like a man looking for family approval. He will be pitching like a man throwing 101 mph who has finally figured out how to stay healthy.
The less-is-more experiment
Weathers has never lacked stuff. Talent was never the problem. The issue has been durability. A flexor strain in spring training 2025 cost him months. A left lat strain during the regular season ended his year after just eight starts. Over the past two seasons with Miami, he made only 24 starts in total.
When the Yankees brought him in, pitching coach Matt Blake and the staff overhauled his between-starts throwing program. The goal was counterintuitive: to help Weathers throw harder by throwing less.
“Some guys that throw hard like to throw a lot, and I think that’s one thing that we’ve found is trying to find ways to modulate the throwing program a little bit,” Blake said during spring training. “Finding ways to take a breather every now and again — it doesn’t mean detrain yourself, but it also means give yourself a chance to recover and then keep building.”
Under the new plan, Weathers no longer long tosses on bullpen days. He caps his flat-ground throws at 90 feet and carefully monitors his total volume. On Saturday at Oracle Park, he made 41 flat-ground throws before a 25-pitch bullpen session. That is 66 total throws. Previously in his career, a bullpen day meant 80 to 100.
Weathers said the adjustment took time.
“It was weird at first, because I love to throw,” he said Saturday. “But now it’s kind of like second nature. We got some internal numbers that have really helped me get in the right direction with my throwing patterns. Everything feels good right now, so got to keep rolling with it.”
Triple digits and uncharted territory for the Yankees lefty
The results of the Yankees’ new program are showing up on the radar gun. Weathers said he is throwing harder than at any point in his career. In his final spring outing Tuesday against the Cubs, he touched 101 mph in the third inning and was still sitting at 98.5 on his 76th pitch.
“That’s uncharted waters for me,” he said.
Among left-handed starters in the majors, only two-time defending AL Cy Young Award winner Tarik Skubal throws harder. This spring, Weathers threw 23 pitches at 99 mph or above and reached triple digits twice. Few starters in baseball, regardless of handedness, can match that kind of velocity.
His arsenal goes beyond the fastball. The Yankees liked his changeup, sweeper, slider and sinker enough to trade significant prospect capital for him. In his 24 starts across the 2024 and 2025 seasons with Miami, Weathers posted a 3.74 ERA with 117 strikeouts in 125 innings.
“Being this early, I’m really encouraged with where my arm health’s at,” he said.
Spring training numbers tell two stories
Weathers’ spring with the Yankees was a tale of extremes. He bookended it with strong outings, giving up one run across a combined 8.2 innings in his first and last appearances. But in three starts in between, he was hammered for 16 earned runs in 8.2 innings on 22 hits, three walks and two hit batters.
The Yankees largely attributed the rough stretch to batted-ball luck. A .434 batting average on balls in play supported that view. He still struck out 21 batters in 17.1 spring innings, and the coaching staff maintained that his underlying numbers and pitch quality were strong despite the inflated 8.83 ERA.
Now the games count. And the Yankees rotation has already set a high bar. Max Fried, Cam Schlittler and Will Warren combined to allow just one run in 16 innings during the three-game sweep of San Francisco.
A tough opener against Seattle
Weathers’ Yankees debut will not come against a soft lineup. The Mariners feature 2025 AL MVP runner-up Cal Raleigh and star outfielder Julio Rodriguez. Seattle is considered one of the favorites for this year’s American League pennant, and this Yankees-Mariners series shapes up as a significant early-season measuring stick for both clubs.
First pitch Monday is set for 9:40 p.m. ET.
Weathers sounded ready when asked about the moment.
“I’m excited,” he said. “It’s been fun being a Yankee in the spring, I can’t imagine during the year. I won’t stop saying it, there’s a sense of pride when you put this logo on and you want to do well for the team and the organization. So I can’t wait for my number to be called and go out there and throw.”
His father will be watching. The Yankees will be counting on him. And the rest of the American League will get its first look at what a healthy, velocity-enhanced Ryan Weathers can do in a game that matters.
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