Pearl Jam and 'Let It Go' in Milan, Italy

For Pearl Jam devotees, a double-encore, 35-song set in Milan, Italy, on Friday night might have seemed par for the course for the veteran band. But a surprise appearance from one Disney song was enough to garner the interest of fans around the globe.

During a performance of one of the band’s most identifiable tracks, “Daughter,” frontman Eddie Vedder offered a surprise nod toward “Let It Go,” the beloved hit from the Disney animated film “Frozen.” The snippet lasted just over 30 seconds (watch a crowd-shot video above).

Since its release as a single in January 2014, “Let It Go” has been nearly inescapable. Sung by actress-singer Idina Menzel, it won the Oscar for best original song at the Academy Awards and peaked at No. 5 on the Billboard Hot 100. Menzel also performed it alongside Jimmy Fallon and the Roots on the "Tonight Show" in March.

Despite the attention the cover has received (nearly 600,000 YouTube views and counting), the song may have been a one-off homage from Pearl Jam. The band, which is touring throughout Europe, did not include the rendition in their following show Sunday night in Trieste, Italy.

Covers have long been a fixture of Pearl Jam sets. Neil Young’s “Rockin’ in the Free World” has been a live staple for years, and the Seattle group has also nodded toward Pink Floyd’s “Mother” and “Rain” by the Beatles on this tour.

Pearl Jam is to be back in the States for an October show in Cincinnati, and is set to play "Austin City Limits" soon after.

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