> ## Content Index > Fetch the complete content index at: https://www.emeraldcityspectrum.com/llms.txt > Use this file to discover other available public pages before exploring further. # What Would a ‘Buyer-to-Buyer’ Trade for Mariners Look Like? - URL: https://www.emeraldcityspectrum.com/buyer-to-buyer-trade-seattle-mariners/ - Published: 2026-07-08T20:39:27.000Z - Updated: 2026-07-08T20:39:27.000Z - Author: Nick Lee - Tags: Analysis, Mariners, MLB Trade Deadline, Luis Castillo It’s almost the All-Star break. That means it’s trade rumors season. It’s an exciting time for all 30 MLB teams. If your team is in contention, excitement builds about which players your team’s general manager might acquire from another team. Fans enjoy conjecturing trade packages that would benefit their team. Even if your favorite team is seemingly out of the race (although with now three Wild Card spots, that pool of teams is smaller than ever), there are still reasons to tune in. Die hard fans of teams not in contention start stalking the prospects of other MLB organizations, guessing which teams might trade for their best big leaguers to merit exciting young talent in return. This season is a bit unique. The American League, as a whole, has been very mediocre. Only one team in the entire AL (Angels) is double-digit games back of a playoff spot. Even the 38-54 Royals are 8.5 games back of the last AL Wild Card spot. This leaves the August 3 trade deadline in a weird spot. That led to Seattle Mariners president of baseball operations Jerry Dipoto having an[ interesting quote on MLB Network Radio](https://sports.mynorthwest.com/mlb/seattle-mariners/seattle-mariners-jeff-passan-jerry-dipoto-trade-deadline?ref=emeraldcityspectrum.com), saying, “I think there are enough contending teams with real holes or needs to fill that you might actually see more action with contender trading with contender like, buyer-to-buyer type trades to fill voids.” Those are the trickiest type of trades to make. Both teams involved have World Series aspirations and are wary of making the wrong move that might cost them a title. They also take the risk of making their trade partner better to where they may meet in the postseason and face the player they just traded away. What would a “buyer-to-buyer” trade look like for the Mariners? Clearly, both teams need to have a surplus of the position the other team needs. For the Mariners, they famously have a surplus in starting pitching, which is the same energy as saying “my lobster is too buttery, my steak is too juicy.” Every team wants that problem. Elsewhere on the roster, there are massive holes. It’s possible they could target a team offering up a [quality outfield bat to help with their woes against left-handed pitching](https://www.emeraldcityspectrum.com/home/seiya-suzuki-seattle-mariners-missing-piece-trade-deadline). But if the extra-inning loss to the Marlins on Tuesday taught us anything, it’s that the Mariners severely lack bullpen depth. They need to find a partner that needs starting pitching but also has depth in the bullpen from which they feel comfortable subtracting. The Atlanta Braves, as of Wednesday, have the best bullpen ERA in the National League. However, their starting rotation has been decimated by injury. Three major pieces of their planned rotation (Spencer Strider, Spencer Schwellenbach, and AJ Smith-Shawver) are all not only on the injured list, but the 60-day IL. There is doubt that any of them will return before August, much less the season at all. They desperately need to add starting pitching ahead of the deadline. Enter the Seattle Mariners. The controversial “piggybacking” situation has been well-documented. Dealing one of their starters for help elsewhere would ease the tension in the rotation while also shoring up a big roster hole in the bullpen. The Braves certainly would not deal one of their top closing options in Robert Suarez or Raisel Iglesias. But acquiring starting pitching comes at a high cost. Even with Castillo struggling this year, he is under contract for another season beyond this and has a decade of a successful track record under his belt. This season, it hasn’t been as solid, with a 4.79 ERA and 83 ERA+ in 82 2/3 innings. It should be noted that Robert Suarez is currently on the injured list. If Atlanta feels he will miss extended time, they may not have the stomach to deal away healthy bullpen arms now. Dylan Lee has been Atlanta’s best reliever that isn’t their closer. With a stifling 1.56 ERA in 42 appearances, he’s been as reliable as they come out of Atlanta’s bullpen. He is a left-handed reliever and to some fans, that may seem redundant with Jose Ferrer and Gabe Speier having solid seasons from the left side of the bullpen. However, if you pop the hood, you can see that Lee has “reverse splits.” Meaning, even though he’s a southpaw, he has virtually the same success against righties as he does lefties, and in some stats, *more* success versus right-handed hitters this season. This year, he has allowed a .398 OPS against right-handed batters and .480 OPS versus lefties with a much better strikeout-to-walk ration versus righties. Let’s build a deal that sends veteran starting pitcher Luis Castillo to Atlanta to give them much-needed rotation help while Lee comes to Seattle to add to the struggling bullpen. Castillo is not cheap, nor will the Braves be free of that contract soon, if they agree to take the full deal. He’s under a big contract (roughly $24.15M in 2026 and 2027, plus a 2028 vesting option). This would not be a straight-up swap. The Braves would hang up the phone before DiPoto or Justin Hollander finish the sentence. For starters, the Mariners should agree to pay down some of Castillo’s salary. Perhaps sending $10 million to Atlanta along with Castillo would help Atlanta shoulder the contract, slightly less than half his salary for next season. That still may not be enough for the Braves to part with one of their top reliable veteran relievers. If the Mariners throw in left-handed pitching prospect Mason Peters (#14 SEA), that might get it done. Peters has logged nearly 45 innings in Single-A this year with a stellar 1.41 ERA so far this season. Lee won’t come cheap. Not only is he a solid reliever, but he is under team control for two more years after 2026 at a reasonable price. He could be a staple in the Mariners bullpen for this entire championship window. That comes at a cost. It’s worth it if Lee can be part of an improved Seattle bullpen on a team with serious World Series aspirations. ### Final Trade Proposal **Mariners receive*: RP Dylan Lee (under contract through 2028 season)* **Braves receive*: SP Luis Castillo + $10 million, and Mariners’ No. 14 prospect LHP Mason Peters*