Mariners Breakdown: Who is new reliever Ryne Stanek?

Mar 8, 2024, 11:05 AM

Ryne Stanek of the Houston Astros in action against the Seattle Mariners on June 6, 2022. (Carmen Mandato/Getty Images)

(Carmen Mandato/Getty Images)

Seattle Sports

The Seattle Mariners have added a new weapon to their bullpen this week, and it’s one that has a chance to be a real impact arm for the M’s.

According to Seattle Sports’ Shannon Drayer, the Mariners are signing right-handed reliever Ryne Stanek, who is 32 years old and most recently pitched for the Houston Astros, to a major league deal.

Drayer: With uncertainty in bullpen, Seattle Mariners sign veteran RHP Ryne Stanek

Stanek has pitched for three teams at the MLB level over seven years, and he was actually a third-round pick of the Mariners in 2010, but didn’t sign and instead went to school and became a first-round pick a few years later.

Three up. Three down.

🔥 @rstanek_55 #ForTheH pic.twitter.com/jAfIQBg7AZ

— Houston Astros (@astros) April 3, 2021

Stanek also has four years of postseason experience thanks largely to him spending the last three years in Houston.

So who is Stanek, and what does he bring to the table for the Mariners? Let’s dive in.

The numbers

Stanek has been a reliable arm during his seven years of MLB experience.

He owns a 3.45 ERA, 1.274 WHIP and 4.14 FIP across 374 career innings. Stanek has excelled at missing bats to the tune of a career 10.5 strikeouts per nine rate, and he’s allowed 6.9 hits per nine, too.

Last year for Houston, Stanek was solid in 55 appearances with a 4.09 ERA, 1.243 WHIP and 4.60 FIP. He allowed 7.5 hits per nine and had the lowest strikeouts per nine clip of his career at 9.1. But his 3.7 walks per nine rate was below his 4.5 career mark.

Based on Stanek’s track record, those 2023 numbers seem to be about what Stanek’s floor is.

As for his ceiling, look just one year prior.

Stanek was one of the best relievers in baseball in 2022. In 50 2/3 innings on the World Series champion Astros, Stanek had a miniscule 1.15 ERA and a 1.226 WHIP and 3.02 FIP. He allowed just 5.9 hits per nine while striking out 10.2 per nine.

Stanek is also someone with “reverse splits,” meaning he has better success against lefties than righties. That’s been the case over his career as lefties own an OPS of .660 against him and righties have a .674 OPS mark. Last year, lefties OPSed .614 off Stanek while righties had more success at .753. For context, the MLB average OPS was .734 in 2023.

At worst, Stanek could be a solid middle reliever for the Mariners who can combat lefties. At his best, especially with injury concerns with Matt Brash and Gregory Santos to start the year, Stanek could be a key back-end leverage arm for Scott Servais’ bullpen.

The stuff

Most relievers are two-pitch guys. Not Stanek.

Stanek is a hard-throwing three-pitch reliever who leans heavily on his fastball. And for good reason.

In 2023, Stanek used his 4-seam fastball 64.2% of the time and it averaged 98.2 mph, which ranked in the 96th percentile in MLB, per Statcast. Hitters had a .220 average against it with a .392 slugging percentage while swinging and missing at it 24.8% of the time.

Going back to the “reverse splits,” a big reason for that is Stanek’s splitter, which is a nasty pitch in the upper-80s to lower-90s. He’s used that mostly to combat lefites, but will throw it to righties, too. Stanek threw the splitter 18.2% of the time last year and allowed only two extra-base hits off it. It had a very high 46.8% whiff rate and hitters mustered only a .189 batting average and .297 slugging percentage when Stanek threw the splitter in 2023.

For righties, Stanek’s slider is his go-to secondary offering. Part of why his numbers were worse in 2023 was because he had far less success with the slider than in 2022. Hitters hit .296 with a .519 slugging percentage off Stanek’s slider in 2023 compared to a .280 batting average and .320 slugging percentage in 2022. But Stanek does get a lot of swing and miss with the breaking ball, as evidenced by a 40% whiff rate with his slider last season.

Three punchouts from Stanek. pic.twitter.com/UvGgkM6Ec3

— Houston Astros (@astros) June 24, 2023

Overall, Stanek gets a lot of swing and miss, with him ranking in the 82nd percentile there in 2023 and 94th percentile in 2022. What’s interesting with that is he doesn’t get too many hitters to chase out of the strike zone as you may imagine, as he had a 30th percentile chase rate in 2023 and 37th percentile in 2022.

Stanek allows a lot of hard contact, ranking 13th percentile in 2023 and 22nd percentile in 2022, and if he’s not punching guys out, most of his outs come through the air. He had just a 4th percentile groundball rate in 2023 and 19th percentile in 2022, so don’t look for him to be the guy coming in when the M’s are looking for a double play ball.

The Mariners picked up a very high-octane arm with Stanek, and he has the secondary stuff to match it, especially when it comes to his splitter. The additions of Stanek and Santos – barring health with Santos and Brash – gives the Mariners a potentially deep and dangerous bullpen late in games with five guys – Andrés Muñoz, Brash, Santos, Gabe Speier and now Stanek – as high-leverage options for Seattle.