San Diego Padres right fielder Fernando Tatis Jr. (23) is congratulated by center fielder Jackson Merrill (3) after scoring against the St. Louis Cardinals during the first inning at Busch Stadium on July 24. Jeff Curry-Imagn Images

San Diego Padres Deal One of Baseball's Best Prospects in Shocking Trade Deadline Move

Originally posted on Minor League Baseball on SI
By Brady Farkas | Last updated Jul 31, 2025 11:16 AM ET

With just hours remaining until the Major League Baseball trade deadline, the San Diego Padres and Athletics have pulled off a massive stunner, with the A's sending All-Star closer Mason Miller to San Diego for a prospect package headlined by the No. 3 prospect in the sport.

Per Jeff Passan of ESPN:

The A's are receiving shortstop Leodalis De Vries, the No. 3 overall prospect in baseball, along with three pitchers from San Diego for Mason Miller and J.P. Sears, sources tell ESPN.

The A's are receiving shortstop Leodalis De Vries, the No. 3 overall prospect in baseball, along with three pitchers from San Diego for Mason Miller and J.P. Sears, sources tell ESPN.
— Jeff Passan (@JeffPassan) July 31, 2025

Miller, 26, is one of the best arms in baseball, and he regularly flashes triple-digit velocity. He's fanned 59 batters in 38.1 innings and is one of the best closers in the entire sport. He's 1-2 this season with a 3.76 ERA, and he has 20 saves in 38 appearances. He struck out 104 batters in just 65.0 innings a season ago. Miller didn't pitch on Wednesday night in a save situation, leading to speculation that he could be dealt.

He'll be under team control through 2029, giving the Padres an opportunity to compete for years to come with him.

De Vries, 18, is already playing in High-A ball. In 82 games at High-A, he was hitting .245 with eight home runs and eight stolen bases, despite playing against players that are significantly older than him. A switch-hitter, he could be a star for years to come, though he isn't projected to make his major league debut until 2027.

The following comes from a portion of his MLB.com prospect profile:

A switch-hitter, De Vries already shows an exquisite knowledge of the zone and will take his walks like he's a player many years older. He needed just a little bit more exposure to California League arms before making the adjustment to their quality, and that speaks well to how he'll handle higher levels. He's proven to be a better slugger from the right side early in his career -- seven of his 11 homers came from the right despite getting 162 fewer plate appearances there -- but he has enough bat speed from the left that splits aren't a major concern.

San Diego is 60-49 this season.

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This article first appeared on Minor League Baseball on SI and was syndicated with permission.

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