Shelton, dressed in a black suit with a red guitar strapped around his neck, and Stefani, clad in a full-length gold dress, took the stage to perform their new duet, "Go Ahead and Break My Heart." Stefani co-wrote the song.

Fans couldn't get enough of the romantically charged performance.

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"The way Blake looked at Gwen when she's singing!! LOVE!" wrote Twitter user @danielleliu0518.

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"Gwen & Blake haven't taken their eyes off each other," @GagaNoir wrote.

– The Cox Media Group National Content Desk contributed to this report.