Mariners Sign Jorge Polanco, Condemn Themselves to Competence

Let’s get this out of the way at the start: The Mariners are pretty good. Their starting pitching is incredible, and some projections systems even think they have a top-10 offense. This is not a Pirates situation, where a core led by Paul Skenes on a league-minimum contract is somehow projected to finish well under .500. In Seattle, the pieces are almost all there. Sadly for fans, “almost all there” might well define this era of Mariners baseball.

The latest expression of Seattle’s complacency came last week, when the team brought back Jorge Polanco on a one year, $7.75 million contract. (The deal is pending a physical.) According to a report from Adam Jude at the Seattle Times, Polanco’s signing means the “Mariners’ roster is effectively set.” For those counting at home, $3.5 million for 37-year-old Donovan Solano, a trade for Austin Shenton, and the Polanco deal represent the entirety of Seattle’s offseason roster upgrades. The Mariners missed the playoffs by one game in 2023 and 2024; they missed it by two games in 2021. They are always good but never great. And the team — or at least ownership — appears totally fine with that.

Mariners president of baseball operations Jerry Dipoto caught a lot of heat for his 2023 comment that “those teams that win 54% of the time always wind up in the postseason,” and in all honesty I think the intent of that comment was widely misrepresented. (The line in that same presser that they were “actually doing the fanbase a favor” a couple days after they missed the playoffs probably deserved more scorn.) But the reason it sticks around, I think, is because the Mariners, as a franchise, seem hellbent on leveraging an excellent cost-controlled core to win exactly 89 games every season.

Since 2021, the Mariners have won 54.47% of their regular season games. Despite sitting at that sweet spot of the projected win totals, year in and year out, where the value of a marginal win is greatest, the organization refuses to spend in free agency to make even a somewhat risky long-term bet.

To the Mariners’ credit, they’ve traded for some impactful players; they even signed one of those players, Luis Castillo, to a nine-figure extension. (Pay no mind to the fact that they’ve reportedly tried to offload the back half of that contract this offseason.) The most recent of these trades brought Randy Arozarena to the club last July. He’ll now spend two more years under team control on contracts that are both artificially suppressed and still somewhat pricey. (Arozarena is slated to make $11.3 million in the upcoming season.)

And there is some reason for Seattle to avoid long-term commitments to any infielders given the prospects coming through the ranks. Jude points out that the state of the major league roster opens the door for top prospect Cole Young to win a job out of spring training, or Ryan Bliss to make a short-term play for the second base gig. Prospect evaluators disagree on the quality of the Mariners’ minor league depth, but at least one sees their prospects as the best in the sport, defined largely by their crop of position player prospects creeping toward the high minors.

It also must be said that to some extent they must account for the contracts of the Mitches. This season, they will spend 18% of their payroll on two players whose projections are uncomfortably close to replacement level: Mitch Garver and Mitch Haniger. At least Garver can slot in as an expensive backup catcher, but Haniger absorbs a roster spot and $15.5 million of precious payroll space, ostensibly limiting Seattle’s ability to splash cash on the open market.

But the Mitches are only a limitation in a world where ownership — led by John Stanton — refuses to entertain anything other than a middle-of-the-pack payroll. Missing the playoffs by one game for the second consecutive year and responding by making Polanco the marquee signing is an abdication of responsibility as stewards of this club. In 2022, the Mariners led all of MLB in operating income. It would be misguided to think that they couldn’t comfortably add $30 million to the payroll to make a push for the division title.

So instead of signing Alex Bregman to fill their third base hole, they brought back Polanco. Third base? Yes, even though Polanco played second base for the Mariners last year, he is reportedly going to slide over to the hot corner this season.

At first glance, this looks like a curious choice. Polanco posted -8 DRS and -10 OAA in his 112 games as a second baseman last season; that latter mark ranked in the second percentile for his position. His arm strength (75.6 mph) would have ranked as the slowest among all major league third basemen. Why make a poor defender with a noodle arm on the wrong side of 30 switch to a position where he’ll have to make even longer throws?

The Mariners, evidently, think it will help “keep him healthier,” according to Jude’s report. I’m not exactly sure I follow the logic there, but I do have an alternative theory for why they think the position switch might suit him.

When I went to Polanco’s Statcast fielding page, I noticed that he rated especially poor when he was moving to his right, and third basemen typically do not have to move much in that specific lateral direction. Perhaps Polanco’s defensive value would improve by eliminating his most glaring weakness.

I wanted to take a closer look. Unfortunately, MLB Advanced Media makes this extremely difficult. My hope was to watch Polanco’s 20 worst plays or so by OAA to identify potential patterns. While MLB does have this sort of information available for outfielders on a play-by-play basis, the situation is slightly more complicated for infielders. For those on the dirt, they provide a long JSON string with OAA value per play, but only some identifying information — the batter handedness, the home park, the launch speed, and the month in which the play occurred.

So in order to figure out which plays of Polanco’s resulted in the most negative OAA, I first had to scrape that JSON string, then convert that JSON string into a workable dataframe. Once I had that data sorted by negative OAA, I had to manually identify every single play by inputting the parameters I outlined above into a Statcast search. In nearly all cases, there was only one play that matched each description, so I could confidently assert which plays aligned with which lines in the data. But please MLB, there is an easier way: Just put the playid in the description! Why are you making me go on a scavenger hunt? Help me help you!

Anyway, I spent a couple hours doing this in order to bring you, my dear reader, only the finest defensive analysis. And thankfully this work wasn’t in vain. I watched all of Polanco’s plays where the batter reached base despite an estimated success rate of at least 70%. That included all seven of his errors as well as 15 plays that were scored base hits.

On three of those hits, Polanco tried and failed to go to his left. Four were hot shots right at him that he couldn’t quite corral. But the majority — nine in all — featured Polanco moving to his right.

Across all the plays I viewed, this was the most common sight:

And this:

And this:

And this:

Polanco won’t have to make plays like these at third base. Is that enough to guarantee success? No. But it’s a reason why he might be better there than up the middle.

But Polanco’s Mariners fate won’t be tied to his defense. It’s the bat that pays his bills, and it’s the bat that will make or break his value to the club.

There is far less mystery with the bat. Polanco’s goal is straight forward: Pull the ball in the air. Kyle Bland’s Batted Ball Metrics app shows the distribution of a batter’s balls in play relative to league average. Polanco’s tells a pretty clear story:

The whole value proposition of a guy like Polanco is his ability to lift balls to the pull side — this is his approach from both the left and right side of the plate. He doesn’t crush the ball, ranking in the 19th percentile in bat speed, but he gets to his power ceiling by attacking pitches out in front with one of the steepest vertical bat angles in the league. He’s even capable of unleashing an uppercut swing on slower velocity at the top of the zone, as Ronel Blanco discovered after hanging a changeup in May:

In his best years, Polanco married this aggressive approach with relatively low strikeout rates; in 2021, when he jacked 33 home runs, he struck out just 18.3% of the time. Because of Polanco’s extreme air approach — over the last three years, he’s hit the sixth-fewest groundballs of hitters with at least 1,000 plate appearances — he’s susceptible to low BABIPs, meaning it’s important for him to put as many balls in play as possible.

As one might expect given Seattle’s extreme park effects, that strikeout rate went running in the wrong direction last season. In Seattle, when batting left-handed, he struck out nearly 37% of the time. Granted, Polanco battled knee and hamstring issues last year, and that strikeout rate ticked down after his return in July. There are stories you could tell to convince yourself that Polanco will return to a league-average level with the stick, and perhaps even be a little better than that.

There’s nothing wrong with Polanco, but there’s something wrong with the fact that he’s the premium roster upgrade for a Seattle team so close to excellence. The Mariners, as always, are just good enough to compete for a Wild Card. Given the core, and given the club’s lack of even a pennant-winning season across its nearly 50 years of existence, “just good enough” is not acceptable.