Mary J. Blige had "so much fun" performing with the Rolling Stones at their 50th anniversary concert last night.
The American R&B star took to her Twitter account to express her happiness after singing with the legendary rockers.
Mary was one of many special guests who joined in the celebration as the band took to the stage at The O2 arena in London. It was the first of two London and three US shows the group has planned.
"So much fun performing in London w/ the @RollingStones! Congrats on your 50th anniversary!!, (sic)" Mary tweeted.
Mary provided vocals for Gimme Shelter during the 23 song set. The rockers were also joined on stage by former bandmates Bill Wyman and Mick Taylor for the first time in more than 20 years.
To mark the band's impressive 50th year together a video clip was played prior to the concert which showed dedications from fans. Stars including Iggy Pop, Sir Elton John and AC/DC's Angus Young explained what the band means to them.
Also taking a talking head role was actor Johnny Depp who described how he feels about Rolling Stones' songs.
"[It's] music that makes you want to do bad things," Johnny said.
During the concert, frontman Sir Mick Jagger jokingly made a reference to the price of tickets. The 69-year-old addressed the crowd directly following reports that prices had ranged from £90 to nearly £400.
"How's everyone in the cheap seats?" Mick asked. "The problem is they're not so cheap!"
The Rolling Stones will play London's O2 arena again on Thursday. They will also perform at the Barclays Center in Brooklyn, New York, on December 8 and at the Prudential Center in Newark, New Jersey, on December 13 and 15.
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