The Seattle Mariners shook up their roster around the trade deadline, acquiring reliever Seranthony Dominguez from the Chicago White Sox in a big trade for starting pitcher Luis Castillo, and bringing in outfielder Taylor Ward from the Baltimore Orioles for reliever Alex Hoppe and two prospects.

And with Brendan Donovan set to return from the injured list on Tuesday as well, the M's roster shakeup hasn't stopped, with Ryan Divish of the Seattle Times reporting that the Mariners are releasing veterans Rob Refsnyder and Mitch Garver.

Here's more of what you need to know:

Now 35 years old, Refsnyder was signed to a one-year deal worth $6.25 million last offseason. He was brought in, specifically, to hit left-handed pitching, but he failed to live up to his previous successes. In 53 games, Refsnyder hit just .140 in total with four home runs and 11 RBIs. He hit only .147 against left-handed pitching and he missed a month with injury.

While the numbers were dreadful in Seattle, Refsnyder is a clear choice to get picked up off the waiver wire by someone in need of his usual skillset. We'll see if he can unlock it elsewhere, and if he does so against the Mariners in a key spot.

Also 35, Garver signed a two-year deal with the Mariners before the 2024 season, struggling to live up to his $24 million contract. But when he signed back with the Mariners on a one-year deal this offseason, it was seen as a much more palatable signing and fans generally embraced having him back.

He hit .175 for the year with four homers and an OPS+ of just 73. He fared better against left-handed pitching, hitting .222 with a .344 on-base percentage. He also had a .659 OPS against lefties, making his release more curious.

Well, we know that Jhonny Pereda is coming up to take the place of Garver. He hit .270 in 19 games earlier this season, hitting two home runs and driving in four runs. He's hit .319 at Triple-A Tacoma with three home runs and will get a chance to contribute more regularly as Cal Raleigh's backup.

As for the rest of the roster? That remains up for debate, but here is what we're thinking:

Raleigh, Josh Naylor, Cole Young, Colt Emerson, Donovan, Julio Rodriguez, Randy Arozarena, Dom Canzone and Taylor Ward make up a core nine position players out of 13 spots.

Pereda makes up 10. Beyond that, the team needs three of Victor Robles, Weston Wilson, Stuart Fairchild, and Leo Rivas. Of course, minor league call ups like Ryan Bliss, Miles Mastrobuoni and Nolan Jones are also possible.

For my money? I'd go with Rivas to play the spare infielder and Robles to be a fifth outfielder/backup centerfielder. For the final spot, I'd lean Mastrobuoni to provide another left-handed bat who could play the infield, but I could easily see it being Jones, who was just acquired in the Castillo trade as well. He has 14 home runs in the minor leagues this season and provides the most clear comp for Luke Raley, who is set to miss the rest of the season in all likelihood.

The Mariners play the Tigers at 6:40 p.m. PT on Tuesday.

The newest edition of the 'Refuse to Lose Territory' podcast is out, breaking down the Mariners trade deadline. You can listen here, or you can watch in the YouTube player below: