Green Day invited a 10-year-old fan on-stage to perform with them during their recent headline show at Outside Lands festival.

The rock trio topped the bill at the three-day San Francisco event last Saturday (August 6), delivering a career-spanning 22-track set on the Lands End main stage.

At one point in the gig, frontman Billie Joe Armstrong singled out a young crowd member called Montgomery – who the singer nicknamed Monty – and asked him to join Green Day for a special performance.

“Do you really know how to play?” Armstrong questioned Montgomery. “Alright, kid – get your ass up here!”

Today (August 11), Green Day shared footage of the wholesome moment on social media. The clip sees Armstrong help Monty put on a white guitar. In another fan-shot video, the youngster enthusiastically fist pumped at the crowd.

The child – who sported an ‘American Idiot’-style black-and-red get-up – then began strumming along to a cover of Operation Ivy‘s 1989 track ‘Knowledge’, before making his way down the runway towards the audience.

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A post shared by Green Day (@greenday)

We Love Montgomery ❤️ Thanks for jamming with us at @sfoutsidelands https://t.co/RhR8fVezFK pic.twitter.com/egPMpW34UA

— Green Day (@GreenDay) August 10, 2022

Following the special performance, Armstrong told the young fan that he could keep the guitar he’d played on-stage, and led a chant of Monty’s name. The trio then moved onto an airing of their classic single ‘Basket Case’.

Green Day have also posted an image of Armstrong and Monty hugging on-stage, captioned: “We love Montgomery [love heart emoji] Thanks for jamming with us at [Outside Lands].” You can see that tweet and the videos above.

Last month saw Green Day play an intimate warm-up show in Chicago ahead of their bill-topping set at Lollapalooza 2022. They took to the stage at the city’s 1,100-capacity Metro venue, veering away from their printed setlist in favour of older and rare material.