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- 🚨Mason Miller Traded to the Padres🚨
🚨Mason Miller Traded to the Padres🚨
The Padres have made the shocking move of the deadline by acquiring star closer Mason Miller for four prospects.
Hello and good morning to you too, AJ Preller!!!!! Trade deadline day has arrived.
As many online have noted, we should really stop calling this deadline day and start referring to it as “AJ Preller Day” because this keeps happening. San Diego continues to make some of the boldest moves in baseball and this one certainly qualifies as such.
The Padres have made the shocking move of the deadline, acquiring star closer Mason Miller from the Athletics for a package of four prospects including our 7th-ranked MLB prospect Leo De Vries.
Mason Miller Traded to Padres
Trade Details

The Padres have gone from a potential seller to seemingly pushing chips forward to compete in a loaded National League this season.
For a team that already had one of the best bullpens in baseball, and limited resources to address some real needs on their roster, Preller just threw caution to the wind, dealing his best overall prospect and three pitching prospects for the 26-year-old flamethrower.
Miller has seen his numbers take a bit of a hit this year, pitching in Sacramento, but he is still one of the best arms in the game. He also comes with four years of control beyond this season.
Mason Miller, welcome to San Diego 🔥
— Just Baseball (@JustBB_Media)
3:22 PM • Jul 31, 2025
Along with Miller, starting pitcher JP Sears is also in this deal, giving the Padres a back-end starter with three years of control beyond this season as well.
So what exactly did the Padres give up, what are they getting, and what’s next? Let’s dive in.
The headlining piece for this deal is one that we weren’t even sure the Padres had been willing to put on the table in their other pursuits, such as their targeting of Jarren Duran over the past couple of weeks. That prospect is Leo De Vries.
De Vries was just ranked as our No. 7 prospect in baseball in our latest top 100 update, making this the best overall prospect who has been dealt thus far by a fairly wide margin.
An 18-year-old shortstop in High-A, De Vries was the top international free agent a year ago, when he signed with the Padres for a $4.2 million signing bonus.
In his first season, De Vries immediately came stateside and played 75 games at Low-A, hitting .237/.361/.441, with 11 home runs and 13 stolen bases. This is a switch-hitting shortstop with power potential…he can do it all.
This year, De Vries has made the adjustment to playing in High-A, and has posted a solid .767 OPS with eight home runs in 82 games. As one of the younger players at the level at 18 years old, these are solid numbers.
Leo De Vries at 18 years old in High-A:
.767 OPS
116 wRC+
31 XBH
14.1% BBThe A's have their new top prospect.
— The Call Up | An MLB Prospect Podcast (@The_CallUpPod)
3:16 PM • Jul 31, 2025
Along with De Vries, the Padres traded three pitching prospects in RHP Braden Nett, RHP Henry Baez, and RHP Eduarniel Nunez to the A’s to complete this trade.
Nett is the top arm in the deal, as he was ranked as the Padres’ No. 5 overall prospect in our last update of their farm system at the end of May. The 23-year-old has pitched to a 3.39 ERA in 17 starts this year, with 86 strikeouts in 74 1/3 innings pitched at Double-A.
Baez has also been pitching in Double-A, where he has thrived, pitching to a 1.96 ERA across 20 starts. A strike-thrower, Baez has found great success this season and could represent MLB starting pitching depth as soon as next season.
Finally, Eduarniel Nunez is a reliever who made his MLB debut this season, appearing in four games, allowing two runs in 4 2/3 innings pitched. Down in Triple-A, Nunez has yet to allow a run across 12 1/3 innings pitched.
Team Fit and Outlook
Dealing De Vries is cashing in on the Padres’ best trade chip. Adding two viable starting pitching prospects in Double-A and a reliever that was good enough to make his debut in your bullpen this year is an absolute haul.
Preller could have shopped this package in a couple of different star pursuits for all we know, but ultimately they landed on making this trade instead of saving this capital to try to land the bat they desperately need.
With that said, the A’s also landed a starting pitcher in this deal, and may have defaulted towards getting the best player available, even if it does not exactly fit their needs as much as pulling off a trade for a Jarren Duran or a Steven Kwan to bolster an outfield that needs another bat.
The Cleveland Guardians are “trying to move” both Steven Kwan and Shane Bieber, per @Feinsand.
— Just Baseball (@JustBB_Media)
5:14 PM • Jul 30, 2025
Mason Miller is an unbelievable talent, but this move is still a bit head-scratching when you factor in team need. The Padres have one of the best bullpens in baseball.
A unit so strong that rumors have been floated that they are looking to trade their closer, Robert Suarez, because they have so much depth when it comes to high-leverage arms.
Robert Suárez now leads MLB with 26 saves this season!
He has the 3rd-most saves in the majors going back to 2024
— Just Baseball (@JustBB_Media)
4:20 AM • Jul 9, 2025
The thought was that the Padres would trade Suarez to help them bring another bat to a lineup that desperately needs one, whether that is in left field, at catcher, or just a DH. Now their need for a bat remains, but they have picked up a luxury reliever instead.
Now, with that said, Miller is very good, and JP Sears is a solid MLB starter that comes cheap (contract-wise) control with three years of control beyond this season.
Miller averages 101 MPH on his fastball. Which says everything you need to know about the A’s closer. There were some reports that teams were looking into the possibility of trading Miller and then making him a starting pitcher next season, something the Padres may certainly explore.
For now, he will likely become their closer, as they may still move Suarez in another trade to bolster other areas of their roster. With other top arms in their bullpen, the Padres can now get creative prior to the deadline to see if they can use that area of strength to get other things done.
One thing they won’t need to address as strongly, though, is their rotation, which gets a decent piece with Sears. The 29-year-old is pitching to a 4.95 ERA this season, but that is with pitching in one of the worst environments in baseball for half his starts in Sacramento.
Last year, Sears pitched to a 4.38 ERA across 32 starts and 180 2/3 innings pitched. He made all 32 starts back in 2023 as well, pitching to a 4.54 ERA. Set to hit arbitration for the first time this winter, Sears gives the Padres a cost-controlled starter, albeit one with the ceiling of a back-end arm.
Evaluating the Deal
Judging AJ Preller before he is done working is a fool’s errand, because often there are multiple moves Preller will make that are all attached. It would make even more sense for Suarez to be dealt now, so that return could offset the steep price the Padres just paid.
Regardless, the best bullpen in baseball just got even better. And the Padres did fill a need to help an injured rotation that needs bodies at this point.
Never to be outdone, this is the biggest trade of the deadline so far, but we still have six hours for Preller, or another GM, to try to top it.
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