World Series Probabilities Shift Dramatically After Hectic MLB Trade Deadline

Despite the lack of huge, Juan Soto-level names being moved at the 2025 Major League Baseball trade deadline, some targeted acquisitions by contending teams had a huge impact on postseason and World Series probabilities.

And it's a sign that certain teams are becoming more and more willing to go "all-in" in a given season in an effort to reward a passionate fanbase. 

Dan Szymborski, the creator of the ZiPS projection system housed at Fangraphs, and someone who provides data and analytics to some of MLB's 30 teams, ran simulations of what new and improved rosters mean for some teams' chances of reaching the postseason and making a deep run.

Spoiler alert: the deadline did not help the Minnesota Twins.

READ: Minnesota Twins Basically Empty Their Roster; Who Were The Deadline Winners And Losers?

But it did help teams like the San Diego Padres, who once again put winning now ahead of future value. For better or for worse.

SAN DIEGO - Manny Machado and Tyler Wade of the San Diego Padres dump a cooler of Gatorade on Jake Cronenworth after a walk-off win against the Milwaukee Brewers at Petco Park on June 20, 2024. (Photo by Matt Thomas/San Diego Padres/Getty Images)

Padres Benefit From Aggressive Trade Deadline

Per Szymborski's projections, the team that most improved its probability of winning the World Series in 2025 was the Padres. How? Because, as he explains, what held San Diego back from being one of the top contenders was a lack of depth on the roster. Both in the starting rotation and throughout the lineup. 

One area where the Padres were already elite was in the bullpen, but new reliever Mason Miller's projections are still so exceptional that adding him improved their pitching depth even more. Had the Padres added just Miller, it would have been exciting but underwhelming. But bringing in Ryan O'Hearn and Ramon Laureano to address weaknesses in left field and at designated hitter cemented the Padres' deadline as baseball's best. 

According to ZiPS, pre-deadline, the Padres had a 3.9% chance of winning the World Series. Post-deadline, it's 7.3%. The Dodgers remain the favorites, but because of San Diego's improvements, their probability dropped from 17.4% to 14.7%. That's also due in part to the fact that the Padres now have a greater probability of winning the division. San Diego's won five in a row while the Dodgers continue to struggle, cutting LA's lead to just three games. While the Dodgers are still overwhelming favorites to secure another NL West title, the Padres went from 11.9% to 20.8% to win the division.

Win the division, avoid an extra series, and your odds of winning the World Series increase.

Beyond the Padres, the Mariners, Phillies and Yankees improved their championship odds 1.1%, 1.0% and 0.9% respectively with targeted additions. Unsurprisingly, Cleveland, St. Louis and San Francisco all saw their playoff percentages drop significantly after either trading away players or refusing to add. 

What this teaches is that there are rewards for improving your team when you have a chance to win. Yes, the Padres sacrificed future value, trading most of their best top 15 prospects. But they draft and make international signings every year, and whose to say they won't replinish their rankings with even better prospects? Not to mention the inherent uncertainty of counting on minor leagues, years away from contribution.

The Padres have a real opportunity to win now, something they can't be sure of in 2030. While many organizations obsess over the excess monetary value young players provide, the fans packing Petco Park are going to appreciate seeing a competitive pennant race now more than seeing the team's owners save a few dollars in 2032. Whether it ends in a championship or not, at least they're trying. Sometimes that's all fans want to see.