MLB Trade Grades: Diamondbacks land bullpen upgrade from Mariners

MLB Trade Grades for the Diamondbacks and Mariners trade sending reliever Paul Sewald to Arizona for a three-player package in return. 

With the Arizona Diamondbacks falling from NL West leaders to four games back of the Dodgers and two back of the Giants in second place, everyone was waiting on the club to make a move, specifically one to upgrade their depth of pitching. Paul Sewald should help with that.

ESPN MLB insider Jeff Passan reported that the Seattle Mariners have agreed to trade the 33-year-old Sewald, a right-handed reliever, to the Diamondbacks ahead of Tuesday’s MLB Trade Deadline.

In return, the D’Backs will send three players to Seattle, a club that is hoping to shake up its lineup and still have a chance to push for a playoff spot over the final two months.

Paul Sewald trade details: Diamondbacks send Top 30 prospects to Mariners

Here’s a look at the full details of the trade with the Diamondbacks and Mariners, as reported by Passan and Ken Rosenthal of The Athletic.

Canzone has been in the majors this season but was still ranked as Arizona’s No. 19 prospect. Big-leaguer Josh Rojas comes over in the deal, as does another lower-end Top 30 prospect in Ryan Bliss. The D’Backs, meanwhile, pick up the much-needed bullpen upgrade they’ve searched for.

MLB Trade Grades: Diamondbacks address massive need wisely

The Diamondbacks ranked 23rd in ERA from their relief pitchers in baseball this season. Their recent decline in the standings, falling to third in the NL West, can at least partially be attributed to the lack of consistency and quality out of the bullpen this season.

Adding Sewald should help with that and, even better, the D’Backs didn’t have to give up a ton to make the trade. The veteran reliever has been a solid reliever for several years now and, though he might not wow you with his velocity or even his overall repertoire on the mound, the results have been there.

Even better, Arizona didn’t have to give up a prospect in its Top 18, meaning they still have plenty of chances to continue upgrading the bullpen and add a starter as well. Furthermore, Sewald still has one arbitration year left on his deal, putting him under club control through the end of next season. That’s a big win for the Diamondbacks trying to push back into a playoff spot.

Diamondbacks Trade Grade: A-

MLB Trade Grades: Mariners upgrade lineup depth, farm system dealing Sewald

Make no mistake, it’s been a nightmarishly disappointing season for the Mariners. But trading Sewald, though he was valuable and oft-used in the bullpen, is not Seattle waiving the white flag. Rather, it’s a smart reshuffling of resources to try and make a late-season push.

Rojas provides the team with much-needed infield depth to provide some more stability in that part of the lineup, Canzone has a ton of pop and upside as a Top 20 prospect from Arizona’s well-built farm system, and the infield depth is furthered by the addition of Brill. Rojas could be key, though.

Despite slashing just .228/.292/.296 this season, he had an OPS of .739 or higher in each of the two previous years with Arizona. He could be a change-of-scenery type of player who could take off with his new club. Giving up a reliever entering his mid-30s just before he’s about to become decidedly less cheap is a smart business move, especially if the Mariners lineup can get some help from this trio of players they just acquired for Sewald.

Mariners Trade Grade: B+