Will One of These Mariners Win the 2025 Cy Young?

The Seattle Mariners find themselves in a remarkable position just 48 games into the 2025 Major League Baseball season. Sitting at 28-20, they currently lead the American League West by three and a half games over both the Houston Astros and the Texas Rangers. Beyond the team's strong overall performance, the Mariners boast two legitimate contenders for the prestigious Cy Young Award this year: closer Andrés Muñoz and starting pitcher Bryan Woo. Both players have been putting up exceptional numbers, and their stories this season offer a fascinating glimpse into Seattle’s bright pitching future.

Understanding the Cy Young Predictor and Its Context

Before diving into the individual performances of Muñoz and Woo, it’s important to understand the ESPN 2025 Cy Young Predictor (CYP) metric. This formula attempts to quantify a pitcher’s value by combining various stats such as innings pitched, earned runs, strikeouts, saves, shutouts, wins, losses, and even a victory bonus for leading a team to a division championship.

The formula is:

• Cy Young Points (CYP) = ((5*IP/9)-ER) + (SO/12) + (SV*2.5) + Shutouts + ((W*6)-(L*2)) + VB (see below).
• VB: Victory Bonus is a 12-point bonus awarded for leading your team to the division championship

While the CYP builds over the season and can surpass 100 points, it’s not a direct indicator of winning the Cy Young but rather a performance index. However, it tends to favor relievers, which is evident when reviewing past years. For example, in 2024, the highest CYP scores were held by relievers like Emmanuel Clase & Ryan Helsley but the actual Cy Young winners were starters— Tarik Skubal in the AL and Chris Sale in the NL. This trend shows that while CYP is a useful tool, it requires context and should be taken with a grain of salt.

Andrés Muñoz: The Dominant Closer

Andrés Muñoz, affectionately nicknamed "Senor Smoke," has emerged as arguably the best closer in baseball this season. Over his first 22 appearances, Muñoz has posted eye-popping numbers that underscore his dominance:

• 1-0 record with 16 saves (leading the league)
• 0.00 ERA over 21.2 innings pitched
• 0.74 WHIP (Walks plus Hits per Innings Pitched)
• Opponent batting average of just .113
• 11.63 strikeouts per nine innings
• 3.32 walks per nine innings
• 28 strikeouts to 8 walks (including 2 intentional walks)
• No home runs allowed
• 16 saves in 18 opportunities, with two blown saves due to unearned runs in extra innings

Muñoz’s performance is not just about raw stats. His impact is visible in advanced metrics too. He leads all MLB relief pitchers with 1.9 Wins Above Replacement (WAR) and ranks 10th among all pitchers in baseball. His Win Probability Added (WPA) of 2.44 is the highest in the league, showing how critical his presence is in tight games.

The Historical Challenge of Relievers Winning the Cy Young

Despite Muñoz’s phenomenal start, history shows that relievers rarely win the Cy Young Award. Since its inception in 1956, only nine relievers have taken home the honor. The most recent was Éric Gagné in 2003, who converted all 55 save opportunities with a 1.20 ERA and 137 strikeouts in 82.3 innings pitched. Before Gagné, Dennis Eckersley won in 1992, posting a 7-1 record with a 1.91 ERA and 51 saves, also snagging the MVP award that year.

If Muñoz keeps pace, he’s on track for 54 saves this season, just shy of Gagné’s 55. Even with two blown saves—which were unearned due to the ghost runner rule in extra innings—his zero ERA and dominant peripherals make a compelling case. As I mentioned in a recent Instagram reply, if Muñoz were to have five blown saves but maintain a zero earned run average over 60 innings, the voters might still seriously consider him for the Cy Young. The context behind blown saves has changed, especially with the ghost runner rule, meaning their impact on award voting might be less severe than in the past.

How Did Muñoz Get Here?

Muñoz’s journey to becoming the Mariners’ shutdown closer began in 2015 when he signed as an international free agent out of Mexico with the San Diego Padres. He debuted in the majors in 2019 but was traded to Seattle at the 2020 trade deadline while recovering from Tommy John surgery. The Mariners acquired him along with Ty France, Taylor Trammell, and Luis Torrens in exchange for Austin Nola and two relievers.

In 2021, Muñoz signed a team-friendly four-year, $7.5 million extension running through this season, with club options for the next three years at increasing salaries. This contract has been a steal for Seattle, as Muñoz has developed into arguably the best closer in baseball, poised to earn a much larger paycheck in the coming years.

Muñoz’s Elite Pitching Arsenal

According to Baseball Savant, Muñoz’s pitching run value ranks in the 93rd percentile overall, with his slider in the top 1% of all baseball. His expected ERA of 1.90 is in the 99th percentile, and his expected batting average against is just .175 (top 3%).

His average fastball velocity clocks in at an elite 98.6 mph, complemented by a whiff rate of 36.6% and a strikeout rate of 35.9%, both in the top 3%. He keeps hitters off balance with a barrel rate of only 2.5% and induces ground balls 75% of the time, which is in the top 1% of all pitchers. Simply put, facing Muñoz means either striking out or grounding out, a nightmare for opposing hitters.

Bryan Woo: The Efficient Ace Starter

While Muñoz has dominated from the bullpen, Bryan Woo has quietly become the Mariners’ ace in the starting rotation. What makes Woo special is not just his performance but his astonishing efficiency and durability:

• Only starting pitcher in MLB this season to pitch at least six innings in every start
• Through nine starts: 2.65 ERA over 57.2 innings
• 0.867 WHIP
• 8.6 strikeouts per nine innings
• 1.2 walks per nine innings
• Strikeout-to-walk ratio of 6.88 (fourth-best in baseball)
• Most efficient starter in pitch count with 13.98 pitches per inning
• Averaging just 89.5 pitches per game, rarely exceeding 100 pitches

This efficiency means Woo consistently delivers quality starts—six to seven innings with fewer than two runs allowed—giving the Mariners a strong chance to win each time he takes the mound.

Overcoming Adversity

Woo’s path to becoming the Mariners’ ace was not straightforward. In 2021, prior to the MLB draft, he underwent Tommy John surgery while playing for Cal Poly. The Mariners selected him in the sixth round of that draft, and since then, he’s blossomed into one of the most effective starters in the league.

Elite Fastball and Pitch Mix

Woo’s fastball arsenal is exceptional. His combined fastball run value (four-seam and sinker) ranks in the 100th percentile across all of baseball. He throws a four-seam or sinker about 67% of the time, yet he limits hitters to a .155 batting average against the four-seam and .254 against the sinker.

His slider is his most effective pitch, allowing just a .056 batting average and an 0.83 weighted on-base average (wOBA), the lowest among his arsenal. This pitch mix and control make Woo a formidable opponent, especially as the Mariners’ rotation has been hit with injuries to key starters like George Kirby, Logan Gilbert, and Bryce Miller.

Why This Mariners Duo Matters

Having both Andrés Muñoz and Bryan Woo performing at this level is a special treat for Mariners fans. Muñoz locks down late innings with dominant closing ability, while Woo sets the tone early as an efficient and effective starter. Their combined presence strengthens Seattle’s chances of not only winning the AL West but also competing deep into the postseason.

With George Kirby returning soon and other starters on the mend, the Mariners’ pitching staff is shaping up to be one of the best in baseball. This tandem of a shutdown closer and a rock-solid ace starter is exactly what teams need to contend in today’s game.

Who Should Win the Cy Young?

The big question remains: should Andrés Muñoz or Bryan Woo win the Cy Young Award this year? Both have compelling cases:

• Muñoz is putting up historic numbers as a closer, with a perfect ERA and a high save total on pace to challenge past greats like Éric Gagné.
• Woo is the most efficient starter in baseball, delivering quality innings consistently and maintaining elite control and strikeout-to-walk ratios.

Ultimately, Cy Young voters will have to weigh the rarity of a reliever winning the award against Muñoz’s dominance versus Woo’s consistency and innings-eating ability. Given the historical precedent, Woo might have a slight edge, but if Muñoz maintains his elite performance and the Mariners continue winning, he could break the long-standing trend.

Final Thoughts

The 2025 season is shaping up to be an exciting one for the Seattle Mariners and their fans. With two pitchers in contention for the Cy Young Award, it’s a testament to the team’s development and scouting prowess. Whether it’s the electric closing of Andrés Muñoz or the efficient brilliance of Brian Woo, Mariners baseball has plenty to cheer about.

As a fan, watching these two excel in their roles provides optimism for the future. Their performances also highlight the changing dynamics of pitching in MLB, where closers can be dominant but starters still hold significant value. Keep an eye on these two as the season progresses—it might just be the year one of them breaks through and earns the Cy Young Award.

What are your thoughts? Should Andrés Muñoz or Brian Woo take home the Cy Young this year? Feel free to share your opinions and join the conversation!