Taylor Swift is usually one half of a high-profile couple but on Friday night (July 13) during her Reputation Tour in Philadelphia, the singer got to be the third wheel.

During a meet-and-greet, two fans of the singer got engaged after a woman's boyfriend popped the question while Swift looked on. "They walk into the meet and greet and he says “We met 5 years ago at the Red Tour” and then..... 😻😻😻😻😻😻😻😻😻😻😻😻😻 #thirdwheel," the singer wrote in the caption of a photo of the three.

In the pictures that Swift posted on her Instagram, the singer looks on in shock as the male fan gets down on one knee to pop the question. The three eventually snapped a photo together where the new bride-to-be showed off her ring.

On Twitter, the man, Anthony, said he and his now-fiancee are "two swifties" who "decided to attend a concert together in 2013." Anthony added, "We fell in love with each other and almost five years later, I'm going to ask her to marry me where it all started. She is my BEST FRIEND and the love of my life."

Already 20 shows into her tour, Swift's trek will pick up again on Saturday night (July 14) at Lincoln Financial Field in Philly. Following tonight's show, the singer will head to Cleveland for a show on July 17 before making stops in East Rutherford, N.J., Foxborough, Mass., Toronto, Canada, Pittsburgh, Atlanta and more.

The North American leg of the Reputation Tour officially ends on Oct. 6 in Arlington, Texas, while the world tour portion of the trek will wrap up on Nov. 21 with a show in Tokyo, Japan at the Tokyo Dome.

Check out photos of the proposal below.

Taylor Swift's 'Reputation' Tour: See All the Celebrity Guest Stars

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