Offense is one area Seattle Mariners GM Jerry Dipoto should not be overly aggressive this summer, though it’s conceivable an upgrade could fall into their laps. Defense should be a major part of the decision to add another outfielder, however, and if that player offers more at the plate, that’s gravy.

The Mariners’ shortcomings all are about run prevention. The club’s pitching staff has been serviceable, ranking No. 9 in the American League in Fielding Independent Pitching and No. 10 in Win Probability Added. The rotation ranks No. 7 and No. 8 in those categories and the bullpen comes in at No. 7 and No. 10.

I provided rankings to those metrics to show where the Mariners are versus those they’re racing against. It’s clear, by any measure, the Mariners need to add help. But there’s another way to help prevent runs, and that’s defense.

While the M’s have improved defensively at multiple positions and overall compared to a year ago, it’s a pitching staff flush with fly-ball type arms and the club is rolling out one of the worst corner-outfield combinations in the circuit.

Seattle’s left fielders have combined for -10 Defensive Runs Saved and the eye test doesn’t save Seth Smith and Franklin Gutierrez. Two weeks ago, the Mariners sent down the lone passable left fielder on their roster — Nori Aoki — who is only slightly better than Gutierrez and wasn’t producing at the plate.

In right field, it’s more of the same with Smith and Gutierrez, but sprinkled in is a dose or two of Nelson Cruz.
The Mariners can not only use an upgrade in the corners — they could end up getting even better offensively in the process.

Let’s get to some names, then. But first, a note: Players on teams right in the thick of even the Wild Card race will not be considered. Things can change in a matter of days and weeks, so we’ll check back on or around July 25 for new additions, but there’s no point in adding predictions of several club’s win-loss records over the next three weeks to this exercise.

Here’s a snapshot view of the relief pitching market, with a special focus on what’s logical and realistic for the Mariners in 2016, while covering the bigger names and why or why not they may be a fit:

Josh Reddick, RF — Oakland Athletics
Reddick missed some time this year but was solid a year ago — .272/.333/.449 in 149 games and is generally considered an average to above-average right fielder. He’s a free agent after the season and will earn about $3.3 million the rest of the way.

Reddick will draw a lot of interest from contenders not willing to pay the price for Jay Bruce or Ryan Braun, but the Mariners do have enough ammo to land such a player if the A’s are OK receiving longer-term outfield or pitching prospects, which is the Mariners’ farm system strength.

Ender Inciarte, OF — Atlanta Braves
Inciarte is mostly a defensive wizard but has produced a career .325 on-base percentage to date. He’s down to .236/.307/.305 for the Braves this season, but would be a more-than-capable backup for Martin in center while providing valuable defensive innings in left and right. He’s a very good baserunner, too, and again, the bat has produced in the past, at least enough to warrant a platoon-type role.

The 25-year-old is likely to qualify for Super Two status after this season but remains a value moving forward thanks to his versatility, defense and speed. I’d bet on the bat some, too. The price tag might be a bit steep for Seattle, however. We’ll see how this one develops.

Melvin Upton, Jr., OF — San Diego Padres
Upton is NOT having a career-saving season in 2016. If .266/.317/.444 is career-saving, then his 2015 triple-slash of .259/.327/.429, which followed .208/.287/.333 and .184/.268/.289 the previous two seasons, actually did the saving.

But Upton can run, defend in left or center — he has no experience in right field but is athletic enough to manage — and he’s hitting enough in combination to warrant playing regularly. The problem here is Upton’s contract, which calls for $8 million over the final three months of this season and another $17.05 million next season. He’s certainly not a $16-17 million player and $25 million for a year and a half of Upton — which at his current rate would provide about 3.0 fWAR.

The Padres recently sent $22 million to the Chicago White Sox in order to rid them of that contract, so it’s conceivable they’d be willing to do so to an extent for Upton. Upton, however, is actually worth something of value in trade return if cash is going to be involved.

Assuming the right balance of salary-mitigation and trade cost, Upton is an ideal fit for Seattle, providing a clear defensive upgrade and enough offense to warrant four days a week in left field and a a start in center here an there when the club wishes to give Leonys Martin a day off versus a tough left-hander.

Charlie Blackmon, OF — Colorado Rockies
Blackmon is about average defensively, only managing in center but fitting well in right and serving as an upgrade in left for Seattle. Blackmon’s bat is a real value, though. He doesn’t rely on Coors Field, hits a lot of line drives, has some legit power — fringe average away from Coors, but far from slap status.

Blackmon is due another $1.75 million this season and has two more rounds of arbitration coming. Next season a salary between $5 million and $6 million seems likely.

The cost may be prohibitive, but this is the kind of player the Mariners should consider this summer, and there’s no question Colorado is a seller.

Steven Souza, Jr., OF — Tampa Bay Rays
Souza, who recently was benched for not hustling out of the batter’s box on a triple, is an interesting possibility. The Rays have no specific reason to trade him other than because they really like the return.

Souza swings and misses a lot — 34.7 percent — but is an average corner outfielder with power and playable on-base abilities. He’s not eligible for arbitration until after next season and would fit nicely in the No. 7-hole in the Mariners lineup. Yes, Souza is from Everett — Cascade High School — and probably isn’t a long-term regular, but he could be a multi-year value for Seattle.

The cost is where I run into problems. The Rays are sellers, but that doesn’t mean ‘trade pre-arbitration players under club control.’

David Peralta, OF — Arizona Diamondbacks
While I don’t believe Arizona will ‘sell,’ per se, a player like Peralta could use used to get something to shore up a weakness now and for next season.

Peralta is pre-arbitration until after next season, but often it makes more sense to deal players that aren’t considered long-term regulars during their zero-to-three period rather than waiting for them to get a little pricey, which limits their value to every club in baseball.

Peralta is passable in center in short stints but handles the corners just fine and offers some offensive help, too. He’s batting .259/.308/.442 this season after dropping a .312/.371/.522 triple-slash last season in a full-time role. For me, Peralta, 28, is best used as a part-time player, particularly as the strong-side platoon piece.

He’s on the disabled list with a back injury, but is expected to start a rehab assignment soon and should be activated in time to be showcased.

The one issue I have with such a player is the 35 percent of the time a left-hander is on the mound. The defense isn’t nearly good enough to make up for the time on the bench or the poor production versus southpaws. The Mariners already have two platoons. Adding another offensive platoon player seems like a non-fit.

Brett Gardner, OF — New York Yankees
Gardner still hits enough to be an overall upgrade for Seattle, but he’s fading defensively a bit the past few seasons and is owed $31.5 million guaranteed through 2018.

It seems far-fetched to suggest the Yankees would send a large dollar amount away in a deal without the return being significant enough — and close enough to the big leagues to help in 2017 as the the roster is built to win now, not in three years, not in five — to warrant it. This is probably where the Mariners jump off the Gardner train.

The Upton situation is different than Gardner’s because the Padres are trying to collect young talent and the Yankees are stuck in win-now mode — even if they deal Aroldis Chapman — because they have $130 million on the books for just eight players next season and the average age of those players is 34.

Why isn’t Jay Bruce on the list? Because he’s an awful defender and isn’t likely to be much better at the plate than the combination he’d be replacing — a portion of the Smith-Gutierrez platoon, sometimes used in left, sometimes in right. And I don’t base the defensive assessment purely on the metrics — which grade him at far below acceptable each of the last three seasons and he’s only trending down. Not to mention he’s not exactly good versus left-handed pitching — .256/.292/.456 this season, .229/.294/.423 career.

Did I mention he’s owed $7.25 million for the rest of 2016, plus his buyout of a $13 million option?

Jason A. Churchill

Churchill founded Prospect Insider in 2006 after getting his start at He spent several years covering prep, college and pro sports for various newspapers, including The News Tribune and Seattle PI.

Jason spent 4 1/2 years at ESPN and two years at CBS Radio prior to joining HERO Sports in July, 2016.

Find Jason's Mariners podcast, Baseball Things, right here and follow him on Twitter @ProspectInsider.