Suárez and Naylor Help Push Mariners’ World Series Odds to 10%, According to Playoff Odds Simulator

Link to Grand Salami Time Playoff Odds Simulator

A Lifetime of Belief & Promise from Video Game Simulations

I’ve been a lifelong Mariners fan ever since I was a kid, mashing buttons on Major League Baseball Featuring Ken Griffey Jr. on the N64. I was lucky enough to grow up watching a roster stacked with legends: Ken Griffey Jr., Alex Rodriguez, Edgar Martinez, Randy Johnson, and Dan Wilson — back when he was behind the plate, not in the dugout.

At this stage in my mid-thirties, I’m a husband and father, my only memory of the Mariners making the World Series… is when my 7-year-old self paused the game and punched in Left, Left, Right, Right, Right, Left, Left on the D-pad — the cheat code that guaranteed Griffey a home run every time he made contact.

Maybe that simulated glory planted a seed. Maybe it’s why, for 27 straight years, I’ve held onto hope — even when reality didn’t cooperate. Whatever the reason, I still believe. I love this team. I love the idea that a mid-market underdog can win it all.

So to satisfy decades of belief (and heartbreak), I built a Mariners simulation — more detailed, and arguably more scientific than FanGraphs — to answer the question we ask every fall: Do the Mariners actually have a shot at the World Series?

Making Big Moves at the Trade deadline

Mariners fans know this story all too well: the team surges late, gives us hope, and then comes up just short. Just last season, we made a major push by acquiring Randy Arozarena, whose energy and clutch performances helped fuel a stronger finish. But even with the late-season magic after the hire of Dan Wilson, it wasn’t enough. We missed the postseason by the slimmest of margins — another entry in a long list of “what could have been” seasons.

With the exception of 2022’s drought-breaking playoff run, the past two decades have been full of heartbreaks that came down to one or two games in the standings. That’s why this year’s deadline was so critical. The front office couldn’t just hope for a hot streak; they needed to decisively upgrade the roster in a way that would move the numbers in our favor.

The Mariners didn’t just make moves at this year’s trade deadline — they made a statement. In Eugenio Suárez and Josh Naylor, Seattle added two hitters who change the shape of the lineup overnight. Suárez brings proven power, plate discipline, and a knack for delivering big hits when it matters most. Naylor adds a dangerous left-handed bat with one of the league’s best contact rates among sluggers, capable of hitting for both average and power. Together, they give the Mariners a more complete, relentless offense — one that can put pressure on opposing pitchers from the first inning to the last.

The Numbers Before the Deals

Before the trades, the Mariners sat just under a 54% win rate — below Dipoto’s stated target — with a total team WAR (Wins Above Replacement) of 26.5 and an 81% playoff probability, according to the Grand Salami Time Playoff Odds Simulator. On paper, those are solid numbers. But in the American League playoff race, “solid” isn’t enough. Mariners fans have lived through too many Septembers where the math still looked fine… right up until we fell short by a single game or two.

The Immediate Impact of Adding Naylor and Suárez to our Playoff Odds

Adding Naylor and Suárez bumps Seattle’s projected WAR to 33.2. That’s a massive 6.7 WAR gain, equivalent to about 6–7 additional wins over a full season. Even in a partial year, that kind of improvement can make all the difference in a playoff race.

Based on WAR-to-win percentage correlation, the Mariners’ expected win rate now projects at 58% the rest of the way. That might not sound huge, but over the course of the remaining games, it’s the difference between chasing a Wild Card spot and winning the division.

Seattle’s new roster WAR of 33.2 now ranks 6th in MLB (previously 11th) and 3rd in the AL. That’s elite territory. More importantly, it signals that this team isn’t just aiming to make the playoffs — they’re aiming to make noise in the playoffs.

Mariners fans have been here before, dreaming of October while knowing how quickly it can slip away. But this year feels different. The numbers are better, the roster is deeper, and the urgency is real. If the simulator is right, the 2025 trade deadline may go down as the moment Seattle stopped chasing and started leading.

The Mariners Season WAR as of last week was 26.7, However, after the trade deadline the new WAR value of the Mariners roster is 33.2 which ranks 6th in MLB (3rd in the AL).

WAR: The Best Predictor of Success within Playoff Odds Simulation

WAR isn’t just a baseball-nerd statistic — it’s one of the most reliable measures of how good a team actually is. Our historical analysis shows that total team WAR has a strong correlation (R² = 0.835) with win percentage… By definition, WAR is an estimate based on players statistics on how many Wins the team should gain compared to a minor league replacement.

The Playoff Odds simulation has two main simulation method options:

1) Record based simulation: Simplified Simulation that determines probability of a win based on the record of the teams within head-to-head matchups

2) Current Roster WAR adjusted Team Simulation: This is the gold standard and sites like FanGraphs would use similar approaches to estimate their playoff odds. This methodology accounts for the recent trades of.Naylor and Suárez for the Mariners, by looking at the value of all individuals on the Mariners current roster and summing up the team WAR. Then we take that WAR and estimate the predicted new team Win % based on the formula in the chart below: Win % = 0.0087*WAR + 0.297. This logic is applied to all MLB teams to determine a current roster estimated win %

Team WAR (The sum of WAR of all players from the season) unsurprisingly has a strong correlation (R²) of .835.

The Simulator’s Verdict

Simulation as of last week

A week ago, before our recent hot streak, when we plug these post-trade projections into our simulator, Seattle’s playoff odds leaped from 81% (with a 5.8% World Series Odds) to 92% (with 7.4% WS Odds) — an 11-point jump. That shift takes the Mariners from “likely” to “firmly in control” of their destiny. It means that even with the inevitable bumps in the road, this team has the depth and firepower to withstand a slump and still finish in playoff position. With the latest projections after the Mariners recent hot streak since the trades, the Mariners now have a 97% chance to make the Playoffs based on the WAR - Roster Adjusted Simulation…. AND a 10% chance to win the world series!

Try the simulator for yourself, and flip between the different prediction methodologies: record based or WAR -Roster Adjusted Based) You can also try “What Ifs” like… what are the Mariners World Series Odds if we sweep the Astros?

Current Simulator Projected (WAR - New Roster Adjusted)

As of August 11th, the latest Simulation shows 10% World Series Odds

For the first time in years, the Mariners aren’t just hoping to sneak into October — they’re built to storm in. The moves have been made. Now it’s time to finish what we started.

-Adam Jacobson