Rock in Rio USA has just confirmed British singer Sam Smith will not be playing the festival next weekend, as he has decided to undergo surgery on his vocal cords. He was set to play on the main stage on Saturday, May 16th, right before headliner Bruno Mars, but he ended cancelling a big portion of his tour, including Australian and American dates.

"I am very upset to announce I have been battling to get my vocal cords better the last 10 days, but unfortunately they haven't recovered and I am going to need surgery," Sam Smith wrote to his fans on his official Facebook page. He admitted to be "gutted" for missing the shows he was scheduled to play and revealed he should be recovered in two months time.

Meanwhile, Rock in Rio USA is replacing him with John Legend, who was set to headline the Mercedes-Benz Evolution Stage (secondary stage) that same night. So Legend will be performing on the main stage as Joss Stone steps up as his substitute and headliner on the Mercedes-Benz stage. Los Angeles-based Mayer Hawthorn fills in the gap left in the line-up.

Sam Smith was one of Rock in Rio's main attractions for its second round, dubbed the "pop weekend", after winning big at this year's Grammy and Brit Awards. Doctors had diagnosed him with haemorrhage to the vocal cords in late April, while still in Australia, and told him he had to stop performing in order to heal; that hasn't work.

The troubling news for the soul singer end up being an opportunity for John Legend, who will get to perform front and center at the festival and continue to ride the wave after winning a Golden Globe Award and an Academy Award for Glory, together with Common, for the motion picture Selma.

As for DJ Mayer Hawthorne, he's a singer and songwriter moving in the "neo-soul" arena, and will take the opportunity to show off his latest studio album, Where Does This Door Go, which was released in 2013.

Rock in Rio USA kicked off in Las Vegas last Friday, welcoming around 37,000 fans to the "rock weekend." The Pretty Reckless, No Doubt, Of Mice & Men, Linkin Park and Metallica were the biggest stars on both days. The show goes on this Friday with pop/country darling Taylor Swift. #Music #Festivities