A few buy-low trade targets for Seattle Mariners to consider

With the MLB season set to hit the midway point this week, the needs for teams that will be buyers at the Aug. 3 trade deadline – such as the AL West-leading Seattle Mariners – are becoming more clear.

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The M’s continue to have a roster that is heavy on left-handed bats and, as seen over the weekend when they faced three straight left-handed starting pitchers from the Boston Red Sox, struggles to hit southpaws.

And with key setup man Matt Brash on the injured list for the foreseeable future and closer Andrés Muñoz sporting an unsightly 5.27 ERA and 1.43 WHIP on the year, Seattle could also use some extra bullpen help for high-leverage situations.

Teams don’t always have to shoot for the moon to get help at the trade deadline. So with that in mind, here are four buy-low candidates from teams outside of MLB’s playoff picture – so guys who could use a change of scenery – that the Mariners could look at ahead of the deadline.

Caleb Durbin, Boston Red Sox

If you watched the Mariners’ last series with the Sox, you might be surprised to find this scrappy infielder on a list of buy-low candidates. That’s because Durbin looked like one of Boston’s best players over the three-game series, hitting 7 for 11 (.636) with a home run, two doubles and two stolen bases to help the Red Sox take the series.

Now, it’s a very small sample size, but any time a right-handed hitter has success like that at the notoriously tough T-Mobile Park, I think it warrants taking some notice. And I think the fact that Durbin is slashing just .215/.269/.361 for a .630 OPS in 68 games this year adds a little more weight to how comfortable he looked during his big weekend in Seattle.

It’s also worth noting that the 26-year-old Durbin has been traditionally better against left-handed pitching (.256/.326/.387 slash line, .713 OPS) since debuting in the big leagues with 136 games with the Milwaukee Brewers in 2025. Against righty pitchers, he slashes .238/.309/.375 for a .684 OPS.

The Mariners’ infield in very left-handed. That’s the side that every current infield starter (J.P. Crawford, Colt Emerson, Cole Young and Josh Naylor) swings from, as does utility man Brendan Donovan, who is currently working his way back from injury.

Adding Durbin, who has played second base, third base and shortstop in the big leagues, as a right-handed bench bat would help balance things out. And it doesn’t hurt that he produced last year in nine playoff games with Milwaukee (.276/.364/.414 slash, .777 OPS, three extra-base hits and three steals), or that he showed some serious baseball IQ in the field on Sunday (see the video below).

Ryan Walker, San Francisco Giants

A 30-year-old righty reliever with a funky delivery, Walker had an excellent 2024 season for San Francisco (1.91 ERA, 0.85 WHIP) but has gone the wrong direction since in terms of production.

The WSU product and Arlington, Wash., native had a 4.11 ERA and 1.27 WHIP in 2025, and he has a rough 5.21 ERA and 1.63 WHIP in 20 appearances this year. In fact, he even found himself back in the minors for a spell due to his struggles.

But Walker has been much better in four appearances since being recalled by the Giants, allowing just one hit, one walk and one hit batter with three strikeouts over 3 2/3 innings.

San Francisco (31-46) is in the midst of a troubling first season under new manager Tony Vitello and seems as likely a seller as any team at the trade deadline. Perhaps getting Walker out of the chaos and bringing him home could benefit both him and the Mariners.

Mark Vientos and Devin Williams, New York Mets

Despite having the highest total payroll in MLB, the Mets are in last place in the NL East with a 34-43 record entering Monday. With not much right going on in the Big Apple, it would make sense for them to offload some players that have been coming up short.

Vientos, 26, is another case of someone who had a breakout season in 2024 (.837 OPS, 26 home runs in 11 games) but has been a negative-WAR player since. This year, he has a .223/.256/.393 slash line for a .649 OPS with nine doubles and nine homers in 63 games.

He’s been a first baseman this year but has played more at third in his career, and even though he doesn’t do much with the glove, he remains a source of right-handed pop.

The 31-year-old Williams, meanwhile, is an experienced closer in the first year of a three-year, $41.8 million contract with New York – which honestly is a no-go. But if the Mets are willing to pay off a good amount of that salary, then it would be an interesting conversation.

While Williams has a 4.81 ERA and 1.52 WHIP, he has converted 11 of 12 save chances. And he still throws one of the nastiest changeups the game has ever seen – it’s nicknamed “The Airbender” and operates almost like a screwball, diving down and across the plate to his arm side.

Considering the issues Muñoz has had this season in converting saves (he’s blown five of his 18 opportunities), it wouldn’t be a bad idea to bring in a former All-Star with closing experience into the fold.

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