The wait is over. The Seattle Mariners finally added the bat to their lineup that fans had been screaming for, and without any surprise, that bat is Brendan Donovan. In a three-way trade with the St. Louis Cardinals and Tampa Bay Rays, the Mariners acquired Donovan, sending prospects Jurrangelo Cijntje, ranked 91st on MLB Pipeline’s Top 100, and Tai Peete to the Cardinals, with third baseman Ben Williamson going to the Rays.
Negotiations around one of the most anticipated and heavily linked players in recent Mariners history appeared to come to a standstill. But following the signing of Eugenio Suárez with the Cincinnati Reds, it felt like there was only one option left on the table. Seattle finally struck a deal, and while they lost talent in the process, the Mariners always expected to pay that price for a player of Donovan’s caliber.
Mariners Get Brendan Donovan from Cardinals
Raising the Offensive Floor
Donovan was always linked so heavily to the Mariners because he checked so many boxes. An All-Star at a good age, with multiple years of team control remaining, he provides elite bat-to-ball skill and rarely whiffs. While Seattle’s high-powered offense carried them to the ALCS last year, the Mariners also finished 2025 with one of the highest strikeout rates in baseball, which significantly lowered their offensive floor during multiple stretches of the season.
Brendan Donovan. Mariner.
? https://t.co/QguvDqPw6K pic.twitter.com/jGYYvMysZb
— Seattle Mariners (@Mariners) February 3, 2026
The goal of the offseason was to raise that floor while keeping the ceiling as high as possible. The Mariners began addressing that by retaining Josh Naylor, and they have now followed it up with Donovan. Donovan fits the exact profile Seattle has been targeting. He ranks in the 95th percentile in whiff rate, 92nd percentile in strikeout rate, 96th percentile in squared-up percentage, and 92nd percentile in expected batting average. This is one of the best pure contact bats in the league, and Donovan fits the Mariners’ needs perfectly.
Despite having such power in their lineup, Seattle was not able to generate as many runs as they should have because they did not have runners on base to maximise the impact of those home runs. Their Zone Contact% was MLB’s lowest at 80.2%, while the whiff rate ranked third-highest in the league at 28.6%. This is a problem that Donovan can fix immediately.
Lineup Fit and Versatility
Donovan will likely solve a recent issue at the top of the lineup and project as the leadoff hitter against right-handed pitching. He hit only nine home runs in 2025, and he also struggled at home in St Louis. While T-Mobile Park is often viewed as a graveyard for hitters, recent left-handed bats like Naylor, Dominic Canzone, and Luke Raley have found success, and Donovan has the potential to reach the 15–20 home run range. That power, however, is not why Seattle made the trade. Donovan will be expected to get on base at an elite clip and rack up doubles, allowing hitters like Cal Raleigh, Julio Rodríguez, and Randy Arozarena to drive him in.
Possible Mariners lineup:
3B Donovan
CF Rodriguez
C Raleigh
1B Naylor
LF Arozarena
DH Refsnyder/Raley
RF Robles/Canzone
SS Crawford
2B Young/Rivas— Buster Olney (@Buster_ESPN) February 2, 2026
Providing the Pathway to Develop Prospects
Donovan’s versatility always made him a better fit than other options like Suarez or Ketel Marte. The Mariners’ front office has spoken at length this offseason about giving young players a real opportunity and not blocking their path to playing time if they are deemed ready. Donovan will likely begin the season at third base with Cole Young at second. When Colt Emerson is ready to take over at third, Donovan can slide to second. He can also play the outfield if both youngsters perform or on rest days, and serve as a DH when needed.
The ability to add an elite bat without blocking top prospects–while easing them into major league roles without excessive pressure–is invaluable. Donovan felt like the final piece of the puzzle for 2026, and the Mariners were finally able to land their man.
The Cost
The Mariners sent Jurrangelo Cijntje, the 91st-ranked prospect on MLB Pipeline’s Top 100, and outfielder Tai Peete to the Cardinals. This always seemed to be as far as the Mariners would go in terms of giving up top 100 prospects, and I predicted this return earlier in the offseason.
Jurrangelo Cijntje
Cijntje is a fascinating pitching prospect with the ability to throw from both sides of the mound, though his upside is clearly as a right-hander. From the right side, he features a 70-grade fastball that can touch 100 mph and a slider capable of missing bats. Mariners general manager Justin Hollander announced that Cijntje would pitch exclusively right-handed during the Cactus League while continuing to work from the left side in bullpen sessions.
While he has mid-rotation upside and strong raw stuff, command remains a work in progress. Still, this is an exciting addition to a young Cardinals pitching core that already includes Liam Doyle, and it would not be surprising to see Cijntje reach the big league level as early as this season.
Tai Peete
Tai Peete, the Mariners’ 2023 first-round selection, is a talented and athletic outfielder with plenty of raw power, plus speed, and a strong arm. He has played well in center field at High-A and carries a very high ceiling. That upside has not yet translated into consistent minor-league production, where he has not posted an OPS above .800. The tools are clearly there, but Peete will need to improve his pitch recognition at the plate, as a 33% whiff rate remains a significant obstacle to reaching his potential.
Ben Williamson to Tampa Bay
Ben Williamson is heading to the Rays, along with another prospect and a compensation pick going to the Cardinals. Williamson is a strong pickup for Tampa Bay. He has Gold Glove potential and is capable of playing shortstop as well, with defense that truly stands out. He features an impressive range, a strong arm, and all the tools of an elite defensive third baseman.
Offensively, Williamson remains very limited with not much upside, but he showed flashes of added power after returning to Triple-A. If that continues, he could quickly find himself making an impact in Tampa Bay. Tampa seems like the right kind of organization that can maximize Williamson’s potential.
The Mariners will now look to 2026, with their roster set up, Mariners fans will be confident this last piece in Brendan Donovan can lead them to another AL West title, but only time will tell.
Main Photo Credit: Jerome Miron-Imagn Images