Gwen Stefani Perfoms on Stage with Boyfriend Blake Shelton at His St. Paul Concert

Blake Shelton’s number one tour groupie is Gwen Stefani.

The couple, who are approaching one year of dating, gave concertgoers at Xcel Energy Center in St. Paul, Minnesota a special treat when the pop star made a surprise cameo at the country crooner’s Friday concert.

The two (Shelton 40 and Stefani 46)  performed their
duet “Go Ahead and Break My Heart” to roaring applause with the mother of three also belting out her solo hit “Hollaback Girl” as well.

When she wasn’t on stage singing with her boyfriend, Gwen was at the side of the stage cheering on Shelton and recording the concert on Periscope for her fans outside of St. Paul.

Earlier in the day, Stefani hinted followers about a surprise appearance when she posted a selfie with the caption “Hi Minnesota” on Instagram, hours before the show. In addition, she shared an adoring photo of her man from their tour bus.

Shelton has invited his girlfriend to join him on many of his shows, most recently his Peoria, Illinois and Oklahoma City, Oklahoma shows.

Things appear to be heating up for the couple, and even though they are not walking down the aisle yet, a source close to the couple told PEOPLE they have talked about their future together.

“Rumors are circulating in their circle that they’ve begun preparations for a wedding,” the source said in August. “There’s no date set, but they’re planning ahead and having fun talking about it … Blake and Gwen are madly in love, committed and planning for a future together,” the source added.