Jorge Polanco carried the Mariners in the first month of the year. His struggles in May have been nearly as extreme.
No player had a bigger impact on the first month of success for the Seattle Mariners than Jorge Polanco. With a whopping 2.19 win probability added, both the quality of his hits and when he hit them provided the M’s with more important and impactful performance than ANY player in MLB through March and April. Just for kick(change)s, the only other player above 2.00 WPA in the season’s first month and change was Andrés Muñoz. If you felt like 2021 was back, you weren’t wrong, friends. But while WPA often follows other actual, direct gauges of performance, it’s not predictive at all. Cal Raleigh, hallowed be his name, had a negative WPA in two of his first three seasons (2021 and 2023), despite being a 4.3 fWAR player with a 113 wRC+ in the latter of those years.
But typically it follows that playing well will improve your team’s chances of winning. For Polanco, what we’ve witnessed in May has been the inversion of most of his outcomes that were so meaningful in March and April. As Ryan Blake noted earlier this week, Polo’s tumble down the performance ladder was to be expected, purely given how unfathomably hot he’d been. Unfortunately(?), it’s not exactly as though Polo is suddenly getting BABIP’d to death on similar results – he’s doing worse and getting particularly bad outcomes.
Specifically, we’re talking about his contact. You never know what version of “best shape of their life” you’re going to actually get with players, but Polanco’s healthy knee genuinely seems to have been rejuvenating. His strikeout and walk rates are back in line with his 2016-2021 self, wherein he was a contact-forward, high-average hitter whose power fluctuated year to year. Impressively, he’s hitting the ball harder than ever while doing it, and that’s not changed in May against the previous month, nor has anything he’s doing physically in any major way.
Baseball Savant
Yes, Polanco’s struck out more in May, but not egregiously so. His 251 wRC+ in March and April precipitating a 34 in May appears to largely be the case of inferior contact, namely that he’s hitting all too many ground balls. Over 60% of his May contact has bombarded the worms of Western Washington with fervent pace. There’s nothing really to say – groundballs are deadly for many hitters, particularly those whose foot speed is now quite poor like Polo. He’s slashing .204/.204/.204 on grounders this year, for a 15 wRC+, well below even the still-awful league-wide total of .245/.245/.267 and a 40 wRC+. Polanco cannot succeed if he cannot get the ball in the air.
FanGraphs
The relationship in the visual above is fairly straightforward. Polo’s entire career has been, like many players, a battle to get the ball in the air (ideally on a line) and into the outfield grass. When he does it, the blue line goes down, and his wOBA (and his wRC+, his BA, his OPS, and yes, typically his WPA) go up along the red line. The first month of 2025 was the best of Polanco’s entire career, and while it wasn’t bereft of grounders, they were under his career average (defined by the blue dotted horizontal line). This month, seemingly just by catching the ball just wrong despite mostly similar process, he’s had one of the worst months of his career, and by far the most groundball-filled.
I’m moving apartments this weekend, and have felt in a haze all week at best, so I’ll level with you. I don’t have a solution here, nor even a cause. I set out on this thinking I might have seen some differences in Polanco’s swing from one month to the next, or that his seemingly nagging injury might be impacting him from the left side now. There’s nothing to indicate to me that that’s true, or at least any more so than it might’ve been. Here’s a grounder from mid-April, in the heart of his torrid start.
And a grounder from a week and a half ago, a month exactly after the first clip.
Looks… pretty much identical. And this laser from last night looked just as good as any contact he hit in his scorching start.
He’s not been pitched dramatically different either. While he got more consistent fare in the heart of the plate and on the outer half, that’s remained predominantly the approach, albeit with a bit more off the dish. That’s led to Polo having less meat to feast on, sure, but he’s walked more and chased less. In what I can identify, this is simply an extreme swing of regression back for Polanco from meteoric heights to deep bore hole lows, neither of which represent the likeliest average but all of which are parts of it. If that’s not satisfying, well, sometimes that’s baseball.