The Sk8er Boi singer surprised fans at Nickelback‘s concert at the Greek Theatre in Los Angeles on Friday. Lavigne, 32, performed the band’s hit Rockstar alongside Kroeger and the whole group. The Canadians were also joined by a fan named Owen, who was plucked from the crowd by guitarist Ryan Peake.
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“You never know who will join us on Rockstar karaoke,” the band tweeted.
“Any stage Avril Lavigne graces is instantly better off for it. Blessed to have had her join us,” the band added in a separate tweet.
Lavigne and Kroeger tied the knot in July 2013 before splitting in 2015. The Boyfriend singer has stayed far way from the stage, due in part to a debilitating battle with Lyme disease.
Nickelback is currently on tour in support of their ninth studio album, Feed The Machine.