Taylor Swift's polite watch party at boyfriend Travis Kelce's NFL playoff game turned into a rowdy tailgate when his brother Jason Kelce showed up. TV cameras caught him celebrating shirtless, but missed so much more.

  • Travis Kelce's Kansas City Chiefs beat the Buffalo Bills 27-24 in Buffalo on Sunday (Jan. 22).
  • Swift was in attendance to support her boyfriend. So too was NFL center Jason Kelce, whose Philadelphia Eagles were eliminated last weekend.
  • Temperatures were below freezing but Jason Kelce took his shirt off mid-game and roared to the crowd.
attachment-Taylor Swift Jason Kelce
Kathryn Riley, Getty Images

For once, Swift wasn't the star attraction in the crowd at a Chiefs game. That's because Jason Kelce stole the show to the point that the rival Bills' fans were rooting for him.

He got started really early by tailgating with fans in the parking lot. Here is video of him drinking out of a bowling ball — raise your hand if you'd love to see Swift do that!

Once the game started, Kelce didn't hide his love for the Chiefs, the team that beat his Eagles during last year's Super Bowl.

Pictures below find him looking very concerned during more tenuous times in the game. Travis scored two touchdowns however, which created a few opportunities from him to celebrate. CBS may have shown you his primal scream but only fans nearby could hear it:

The best part came when Jason Kelce spotted this Taylor Swift fan's sign.

He'd already used the window to the stadium suite as his personal entrance a few times, so it wasn't a big thing to see him hop out once more to take selfies with fans who shouted "You're the best!"

When it approached a young fan dying to meet Swift, he may have endeared himself to the Bills Mafia for life. Watch as he picks her up to show Swift the sign.

The Kelce parents were also in attendance for the game, after which Bills fans threw snowballs at the winning team. We're still searching for video of the afterparty.

Jason Kelce, Taylor Swift at the Chiefs-Bills NFL Playoff Game

Singer Taylor Swift was joined by boyfriend Travis Kelce's brother at an NFL playoff game between the Kansas City Chiefs and Buffalo Bills in Orchard Park, N.Y. on Sunday (Jan. 21). The party got kind of wild!

Gallery Credit: Billy Dukes

PICTURES: Taylor Swift Attends the Kansas City Chiefs' Freezing Game Against the Miami Dolphins

Taylor Swift wore a Travis Kelce jersey as she cheered on her boyfriend during the Kansas City Chiefs' freezing-cold game against the Miami Dolphins on Saturday (Jan. 13.)

Gallery Credit: Carena Liptak

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