Sam Smith delighted fans in Locarno, Switzerland on Wednesday night (08Jul15) by calling on fellow soul singer John Legend to join him onstage for a special duet.

The musicians were among the acts on the opening day's bill for the 2015 Moon & Stars Festival and they decided to treat fans to a new rendition of Smith's Lay Me Down.

The Brit later shared an image of the pair harmonising at the show on Instagram.com, captioning the snap, "I don't think I'll ever get used to singing with my idols. Thank you for tonight @johnlegend".

The All of Me star also uploaded an image of the singers performing together, and tweeted, "Just sang 'Lay Me Down' live with @samsmithworld at the #moonandstarsfestival2015 (sic)".

The concert was made all the more special for Smith's fans as the gig was one of his first shows since undergoing vocal cord surgery in May (15). He made his official comeback at the Forest Live outdoor concert in Suffolk, England on Sunday (05Jul15).