Taylor Swift's relationship with Kansas City Chiefs tight end Travis Kelce has now officially gone international.

Kelce jetted out to Buenos Aires, Argentina to watch Swift perform the second of her three scheduled Eras Tour stops in the city on Saturday night (Nov. 11.) Not only did fans spot him watching the show from the VIP tent, but Kelce was also at the center of some of the show's most-talked-about moments.

Coy looks, subtle smiles and winks between Swift and Kelce were favorite choices for fans' highlight reels after the show, as was an iconic post-show kiss -- the first full-blown smooch fans have seen from the couple ever since rumors rumors starting swirling this summer.

But arguably the most unforgettable moment of the evening came during Swift's performance of "Karma," when she dropped a lyric change that seemed to catch everybody by surprise, including her backup dancers and even Kelce himself. "Karma is the guy on the Chiefs / Coming straight home to me," Swift sang.

The crowd went wild, of course, and so did "the guy on the Chiefs" himself. Fan-captured video of the moment shows Kelce grinning and appearing to blush as he covers his face with his hands. Kelce was standing in the VIP tent next to Swift's father, Scott Kingsley Swift, who applauded and grinned in shock at the moment.

Kelce is currently enjoying playing the role of supportive boyfriend during Swift's new international Eras Tour leg. It's a role reversal from a few weeks ago, when Swift attended several Chiefs games during her break from tour.

Swift's recently-launched South American dates are just the beginning for the international run she's got planned. Swift is currently still in Buenos Aires, playing a makeup show on Sunday night (Nov. 12) after one of her three scheduled shows in the city was canceled due to inclement weather. After that she'll make stop in two different cities in Brazil before heading for Japan, Australia, Singapore, France, Sweden and many more countries.

Pictures: Taylor Swift at the Kansas City Chiefs Game (Oct. 22)

Taylor Swift was very distracted at the Kansas City Chiefs game on Sunday (Oct. 22) in Kansas City. Honestly we can't blame her.

Swift and Chiefs' tight end Travis Kelce are dating and she's attended several of his games. Brittany Mahomes and her two kids joined her in the press box this week.

Gallery Credit: Billy Dukes

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