Yankee playoff tickets are being restricted to fans from only four states (sorry, Massachusetts)

If you were planning to road-trip down from Boston to watch the Yankees and Red Sox battle it out in the Bronx, you might want to keep your Fenway chants at home. The Yankees have slapped some borders on their postseason tickets, and only residents of New York, New Jersey, Connecticut and Pennsylvania are allowed to buy directly through Ticketmaster.

That means if your credit card billing address screams Massachusetts—or Vermont, or Canada, or just about anywhere else—your order will be canceled. The policy isn’t exactly new; the Yankees say they’ve used it in recent postseasons as a way to curb scalping and give priority to local fans. Jason Zillo, the team’s vice-president of communications, insisted it’s less about blocking Red Sox Nation and more about keeping bots from scooping up seats. “We are one of dozens and dozens of professional sports teams that do this. If the zip code is in Wyoming, chances are higher they won’t be attending the game,” Zillo told the New York Times.

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Try telling that to Sox fans who took it personally. “They’re scared,” Will Ross, 22, who made the drive from Worcester with a buddy for Game 1, told the Times. “It’s a weak move,” added his friend Ian Inangelo. Neither seemed deterred—like thousands of others in Boston caps, they simply found tickets on resale sites instead.

Indeed, the strategy didn’t stop Red Sox fans from making themselves heard. During Tuesday’s Wild Card opener, Yankee Stadium’s 47,000-strong crowd was mostly Bronx Bombers faithful, but there were enough visitors to belt out “Let’s go Red Sox” chants, even if they were drowned out until Boston’s 3-1 win gave them the last word.

The Yankees insist this isn’t about muzzling the opposition, but history suggests the move is part of a larger tradition in sports. Teams across leagues have experimented with residency-based ticket restrictions in major games, aiming to preserve home-field advantage. It rarely works perfectly, since plenty of rival fans live within the designated zone (hello, Red Sox expats on Long Island). And of course, the secondary market makes the whole policy more symbolic than airtight.

Still, it does add one more layer to the century-old rivalry. The restriction certainly didn’t keep Massachusetts fans from showing up again Wednesday—only this time they went home unhappy, as the Yankees evened the series with a Game 2 win.