Miranda Lambert and her boyfriend, Anderson East, gave fans in Louisiana a surprise on Sunday night (March 12), when East unexpectedly joined Lambert for a cover of the Faces classic "Stay With Me."

Lambert is currently on the road on the Highway Vagabond Tour in support of her most recent album, The Weight of These Wings, and fans who attended her gig in Bossier City, La., got an extra special show. In the fan-shot video above, East and Lambert try out their dance moves as her band light into the bluesy rocker, which was written by Rod Stewart and Ronnie Wood and released on the Faces' classic 1971 album A Nod Is as Good as a Wink ... to a Blind Horse.

The lyrics are unabashedly sexual, and Lambert and East definitely play on that in their performance, turning in a flirtatious, touchy-feely performance that lets their real-life chemistry shine through. Lambert even lays a kiss on East as he approaches her onstage, and the audience sure seems to be enjoying the performance. It's unexpected, fiery moments like this that make Miranda Lambert tickets among the most sought-after in country music.

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Lambert and East first revealed their romance in January of 2016, and they've appeared onstage together several times since then. Lambert joined East for a Valentine's Day performance in 2016, and she also joined him onstage to perform "My Girl" at a show in Los Angeles.

More recently, East joined Lambert and her father onstage at a tour preview show in January, singing an old spiritual-turned-civil-rights-anthem titled “Woke Up This Morning (With My Mind Stayed on Freedom).”

Lambert's Highway Vagabond Tour also features Old Dominion and 2017 Taste of Country RISERS artist Aubrie Sellers. The tour continues through March 19, and Lambert has a number of festivals and shows booked for the summer, too, including a headlining set at the Taste of Country Music Festival in June.

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