A surprise marriage proposal behind the scenes at " Good Morning America" today put a diamond ring on one woman's finger, thanks to her girlfriend and none other than this summer's hottest music duo, Macklemore and Ryan Lewis.

Macklemore and Lewis were on hand in Central Park to perform live for the "GMA" Summer Concert Series. As nearly 5,000 of the duo's fans crowded the stage, one fan in particular stood out.

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The fan, Val, held a sign that read "Can I Propose to My Girlfriend On Stage?" The sign was printed on rainbow-colored poster board, a nod to the couple's sexual orientation and to "Same Love," Macklemore and Lewis' hit song that is a tribute to marriage equality.

Kara, Val's girlfriend, did not see the sign her girlfriend was holding up behind her and suspected nothing.

Tom Kelly, the stand-up comedian on hand to entertain the crowd, did notice the sign and suspected he had a chance to make the proposal happen.

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"I pulled Val and Kara up to the stage," Kelly, told Goodmorningamerica.com by email. "In front of over 5,000 Macklemore fans, Val pulled the trigger."

"Val had a ring ready to go," Kelly wrote. "It was my first time officiating an engagement in seven years of doing warm up for TV shows."

Also watching the proposal take place was "GMA" co-anchor Josh Elliott who invited the newly engaged couple to watch the rest of Macklemore and Lewis concert from the stage.

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After the show the pair got to meet Macklemore, who will perform "Same Love" with Lewis at the 2013 VMAs on Aug. 25 on MTV.

Macklemore celebrated the happy moment with pictures and hugs with Val and Kara.