Blake Shelton and his longtime girlfriend Gwen Stefani joined the lineup of all-star performers on The Voice on Tuesday night (May 19), performing their No. 1 hit "Nobody But You" for front line workers at an Oklahoma food bank.

The couple performed the hit duet from Shelton's Ole Red venue Oklahoma, where they have been in quarantine with her family recently at his ranch. They gave the remote performance for the workers at the Regional Food Bank of Oklahoma, which Shelton has been supporting during the coronavirus (COVID-19) pandemic.

The duet was one highlight of the finale, which also included Shelton performing the John Mellencamp classic "Authority Song" with Todd Tilghman. He also joined Toneisha Harris to perform Fleetwood Mac's "Don't Stop," while Lady Antebellum performed remotely from home, singing their new single, "Champagne Night."

Bon Jovi and the Jonas Brothers were also among the all-star lineup for the Season 18 finale, which ended with Tilghman being crowned the new champion

Shelton and Stefani have been keeping busy during their time in quarantine. They've made a number of from-home TV appearances to perform "Nobody But You," and Shelton has also made a change to his appearance.

The country superstar revealed that he and Stefani had decided he should grow his mullet back in March, as the country was in the early stages of social distancing.

"I am growing the mullet back as a symbol of hope or some s--t like that," he posted to Twitter on March 17. "Anyway it's coming back! For real. Stay tuned."

Shelton posted the first pictures of his new mullet on March 26.

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