HOUSTON — The Houston Astros and the Washington Nationals are duking it out for world baseball domination, but they're not the only ones locked in the Texas-to-DC rivalry!

The two cities' mayors are betting on barbecue and local breweries are wagering a sudsy swap on making each others' beers.

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Even the resident visitors bureaus are getting in on the action!

On Tuesday, both @washingtondc and @Visit Houston posted videos on Twitter showing how each bureau taunted the other (all in good fun ... we assume!)

"Did @washingtondc just send us Baby Shark? 💀" Houston tweeted.

The Nats' official-unofficial mascot shows up at VisitHouston's offices, putting front and center the do-do-do-do-do-do jingle that's become a rallying cry for Nationals outfielder Gerardo Parra and the entire Washington DC fan-base.

In return, DC was gifted a box full of astronaut ice cream -- a nod to Houston's NASA roots -- and a note that read "Just in case you have to wait another 86 years... #TakeItBack #GoStros"

"Oh. It's on," DC wrote.

Game 2 of the World Series is Wednesday night. First pitch is at 7:07 p.m. CST.

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