Brendan Donovan Trade Grades: Mariners Land Versatile Threat in Three-Way Deal

Seattle landed the 2025 All-Star from the Cardinals in a three-way trade that included the Rays. Here’s a look at the grades for each team involved.

The St. Louis Cardinals sent second baseman Brendan Donovan to the Seattle Mariners as part of a three-team trade. | Eakin Howard-Imagn Images

The Mariners just landed a big piece for their lineup as they try to push their way to the top of the American League.

After making a run to the ALCS in 2025, Seattle has made a few moves to solidify itself as a World Series contender in ’26. After re-signing Josh Naylor, the Mariners have now landed All-Star infielder Brendan Donovan from the Cardinals as part of the three-team trade that included the Rays.

Donovan is a versatile defender with a knack for getting on base. St. Louis had been engaged in trade talks to move him for months, and Seattle won the battle to land him. On the surface, it looks like an outstanding fit for a decent price.

Mariners, Cardinals, Rays grades in Brendan Donovan trade

Mariners receive: INF/OF Brendan Donovan
Cardinals receive: RHP Jurrangelo Cijntje, OF Tai Peete, OF Colton Ledbetter, two Competitive Balance Round B picks
Rays receive: 3B Ben Williamson

Mariners grade: A-

This is quite a get for the Mariners, who landed a versatile on-base machine to put in front of the thumpers in the team’s lineup.

From mid-June on, Donovan led off most games for the Cardinals, and it’s not hard to see him fitting that role for Seattle. With guys like Julio Rodriguez, Cal Raleigh, Josh Naylor, and Randy Arozarena hitting behind him, Donovan’s value could skyrocket.

A seventh-round pick in the 2018 MLB draft out of South Alabama, Donovan has developed into one of baseball’s most well-rounded players after four big league seasons. The 29-year-old was an All-Star for the first time in 2025 and finished the season slashing .287/.353/.422 with 10 home runs, 50 RBIs, a wRC+ of 119 and 2.9 fWAR in 118 games. Donovan only struck out 67 times while garnering 42 walks. He missed a chunk of games late in the season due to a groin injury.

Donovan’s career .361 on-base percentage makes him a perfect fit for Seattle’s offense. He primarily played second base last season, but has made 162 career starts in the outfield, plus 29 at third base, 12 at shortstop, and 16 at first.

In addition to his fit with the team, Donovan is under team control through 2027 and the Mariners didn’t have to give up a top five prospect from their farm system to get him.

This is another piece in what should be an outstanding lineup for Seattle, and the cost was worth it..

Cardinals grade: B+

The Cardinals wanted to get younger and turbo-charge their rebuild this offseason by moving off aging veterans with, in some cases, big contracts. Mission accomplished. Donovan is the latest to move after Sonny Gray, Willson Contreras, and Nolan Arenado were all traded earlier this winter.

The Cardinals got a solid return for Donovan. Jurrangelo Cijntje is the prize of the trade, as the switch-pitcher has developed into more than a novelty. Seattle made him the 15th overall pick in the 2024 MLB draft, and he has continued to pitch from both sides in the minors, though he’s better as a righty. During his first professional season in 2025, the Mississippi State product went 5–7 with a 3.99 ERA, 1.22 WHIP and 120 strikeouts against 51 walks in 108 1/3 innings. He reached Double-A by the end of the season.

Cijntje is a bit undersized at 5’11”, but from the right side, he can get his fastball into the upper-90s, and has a hard slider that can reach the low-90s. Seattle planned to have him work only as a right-handed starter in spring training, so it will be interesting to see if the Cardinals go in a different direction.

St. Louis also landed Tai Peete, who was the 30th pick in the 2023 draft. Peete is an athletic outfielder Seattle snagged out of the high school ranks, but after two solid minor league seasons, he struggled at High-A last season. In 125 games, Peete slashed .217/.288/.404 with 19 home runs, 63 RBIs, and 162 strikeouts against 46 walks. He added 25 stolen bases, but his wRC+ was a dismal 79. He has a ton of power and speed, but last year’s 30.6% strikeout rate is a problem. There is a ton of potential here, but Peete has to make more consistent contact.

Outfielder Colton Ledbetter will arrive from the Rays as well. A second-round pick in 2023, Ledbetter also went to Mississippi State. Last season, the 24-year-old slashed .265/.337/.378 with seven home runs, 49 RBIs, 37 stolen bases and 128 strikeouts against 51 walks over 128 games at Double-A. Ledbetter has solid tools across the board, but wasn’t one of Tampa’s top 20 prospects. He’ll need to show more power to increase his ceiling and have a shot as a big league regular.

The Cardinals will also receive two competitive balance picks in the 2026 draft. This is a solid haul for Donovan, whom the team was trying to move all offseason. There is no marquee prospect, but getting three players and two picks inside the top 75 in the draft is good work by the front office.

Rays grade: C

Ben Williamson, a glove-first third baseman, is set to move from the Mariners to the Rays. | John Froschauer-Imagn Images

The Rays worked their way into this deal and were able to get a low-cost piece without giving up too much.

Williamson made his MLB debut last year and struggled at the plate. He slashed .253/.294/.310 in 85 games while hitting just one home run with 21 RBIs and a wRC+ of 76. The 25-year-old is a high-contact, low-power guy who is an outstanding fielder at third base. Williamson’s defense is his calling card, and he’s a hit over power guy, as his nine home runs in 188 minor league games show. He may eventually become more dangerous at the plate. In 52 Triple A games last year, he slashed .314/.392/.462. If he can become a high OBP guy at the big league level, he may stick in Tampa Bay’s lineup.

He’s probably worth Ledbetter and a Comp. B pick, but won’t move the needle much unless his bat becomes more dangerous.

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