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RosterPHIAug 30, 2026, 8:23 AM EDTSignal confidence 85%

Tristan Peters purchased by White Sox after December DFA by Rays

The outfielder was designated for assignment by Tampa Bay in December before Chicago acquired him over the offseason, per FanGraphs.

Posterior generated visual for Philadelphia Phillies: Tristan Peters purchased by White Sox after December DFA by Rays

The White Sox purchased Tristan Peters' contract from the Tampa Bay Rays over the offseason, FanGraphs reported, after the Rays had designated him for assignment in December. The outfielder is now with his fourth organization since being drafted by Milwaukee in the seventh round out of Southern Illinois University.

What happened

Peters was designated for assignment by Tampa Bay in December, per FanGraphs. The White Sox then purchased his contract from the Rays over the offseason, bringing him to Chicago's South Side. The transaction gave Peters a path to the major leagues after he had been unranked as a prospect when he was first profiled by FanGraphs in August 2022.

The outfielder's journey through four organizations began when Milwaukee traded him to San Francisco at the 2022 deadline in exchange for Trevor Rosenthal. He eventually landed with Tampa Bay before the Rays moved on in December, opening the door for Chicago to acquire him.

Why it matters

The purchase represents a low-risk acquisition of a player whose raw tools have developed considerably since his days as an unranked prospect with plenty of edges to smooth out. FanGraphs noted that Peters possessed potential even when his profile was modest, and the White Sox are now the beneficiaries of that development work done across three previous organizations.

For a rebuilding club, adding a player through this route costs only the purchase price and a 40-man roster spot. Peters did not require a trade package or a waiver claim, just the willingness to take on a player another organization had designated for assignment two months earlier.

The timing of the December designation for assignment is notable. Teams often make 40-man roster decisions in November and December to protect prospects from the Rule 5 draft or to clear space for offseason additions. The Rays, known for aggressive roster management, evidently saw a better use for the spot Peters occupied.

The numbers

Peters is slashing .279/.344/.468 with a 128 wRC+ over 408 plate appearances this season, per FanGraphs. The wRC+ figure indicates he has been 28 percent better than league average at the plate, a remarkable outcome for a player who was available for purchase just months ago.

FanGraphs reported that Peters homered in a stretch of consecutive games on Thursday, matching a franchise record shared by seven other players. Munetaka Murakami is among those who share the mark.

The production represents a significant return on investment for a player acquired via purchase rather than trade. The White Sox did not surrender prospects or take on salary in a deal; they simply claimed a player another organization had moved off its 40-man roster.

Where the club stands

The Phillies enter Sunday with an 80-62 record, second in the NL East and four games behind the division leader. They hold the second Wild Card spot, games clear of the cut line, and carry a one-game winning streak into their series finale at Angel Stadium.

Zack Wheeler is scheduled to start Sunday against the Angels and Yusei Kikuchi. The club then travels to Arizona for a two-game set, with Aaron Nola and Jesús Luzardo slated to pitch the first two games of the series against Brandon Pfaadt and Eduardo Rodriguez.

The Phillies' roster decisions in the coming days will be shaped by the September 1 expansion, when active rosters grow from 26 to 28 players. That additional flexibility allows clubs to carry extra depth without sacrificing bullpen arms or bench options, a luxury that becomes particularly valuable as the schedule tightens and the postseason picture clarifies.

What we don't know yet

FanGraphs did not specify the exact date of the contract purchase beyond "over the offseason," leaving the precise timing of the transaction unclear. Whether the White Sox claimed Peters off waivers after the designation for assignment or negotiated a purchase after he cleared waivers and was outrighted is also not detailed in the report.

The financial terms of the purchase were not disclosed. Minor-league contracts purchased and added to the 40-man roster typically carry major-league minimum salary obligations once the player is called up, but any signing bonus or incentive structure remains unreported.

It is also unclear what prompted Tampa Bay to designate Peters for assignment in December. The Rays' 40-man roster situation at the time, whether they needed the spot for a specific acquisition or simply saw a player they no longer valued, was not addressed in the FanGraphs report.

What to watch

Peters' performance over the final month will determine whether he remains part of Chicago's plans beyond this season or becomes a trade candidate himself. A player with a 128 wRC+ and power production on a rebuilding team is precisely the kind of asset that contending clubs seek at the deadline, though his service time and team control will shape his trade value.

The White Sox will also need to manage their 40-man roster carefully as they evaluate which players from this season's group merit protection heading into the offseason. Peters, having already been designated for assignment once, knows the precariousness of roster spots in December.

For the Rays, Peters' success in Chicago will serve as a reminder of the risks inherent in aggressive roster management. Tampa Bay has built a model on maximizing value from overlooked players, but the designation for assignment process occasionally allows a useful player to slip away. Whether the Rays needed the roster spot for a move that justified losing Peters will be a question worth revisiting as the season concludes.

The September roster expansion will give both clubs additional flexibility to evaluate players without the same roster crunch that defines the summer months. For Peters, the extra spots mean more opportunities to build on the home run streak that has him tied for a franchise record and more plate appearances to prove that his breakout is sustainable.

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Phillies: Tristan Peters purchased by White Sox after December DFA by Rays