Is MLB Due for a Second Half — and October — of Parity?

The betting markets still consider the Dodgers huge favorites. But a weak group of top first-half teams seems to be foreshadowing old-school chaos instead.

Shohei Ohtani of the Los Angeles Dodgers reacts as he bats against the Milwaukee Brewers during the third inning on July 08, 2025 in Milwaukee. (Patrick McDermott/Getty Images)

Open up the Polymarket futures for this year’s World Series winner,¹ and you’ll be greeted with odds that, in scale at least — if not the specific teams (hello, Tigers) — wouldn’t surprise anyone who hasn’t been paying attention since that hot-stove kerfuffle over the Dodgers being too dominant on paper for the good of the game:

Source: Polymarket

A 30 percent chance for the favorite at midseason is something we might expect from the NFL or NBA — but not necessarily baseball, where the best team tends to win a lot less often (and where purely statistical models tend to list no team higher than 20 percent or even the mid-teens to win it all at this phase of the schedule).

There are certainly reasons to think the Dodgers might end up on top again, given their star power (especially when/if healthy) and the depth they can throw at problems that other teams simply can’t. But as we approach the All-Star break, there hasn’t been much else to suggest that this 2025 season won’t be a wide-open affair.

The biggest flashing indicator for this might simply be the leaguewide distribution of teams so far. As of Thursday, MLB’s best winning percentage belonged to the aforementioned Detroit Tigers, at .628. While that sounds pretty good — .628 equates to 101.7 wins per 162! — it’s fairly common for the leading team in baseball at the All-Star break to be much higher than that before second-half regression to the mean sets in and drags outliers back down to earth.

From 1996 — the first full season² after the 1994 players’ strike — through 2024, the team with MLB’s top record has averaged a winning percentage 22 points higher (.650) than the Tigers’ current mark. And in fact, each of the top four teams this year are weaker in that regard than the previous post-strike average: