IT HAS not been the best of months for R&B superstar turned pop phenomenon Rihanna. First she was forced to cancel some of her scheduled appearances in Sweden after being hospitalised with the flu, then she admitted dashing off stage during a concert in Portugal to spew. Nice.

The gruelling tour schedule, which began in June, is clearly taking its toll on the singer, yawning during a show at The O2 arena.

While she seemed to have perked up a bit for her final performance at the Greenwich venue, the cracks were all too clear to see at times, only half singing some of her hits and instead holding the mic up to the crowd, expecting them to scream the missing lyrics like a 20,000 strong karaoke singalong.

Not that her fans minded, despite her being 30 minutes late.

With lighting bathing the stage in a riot of camp colour, she made her entrance with all guns blazing, emerging from a giant neon-lit hamster ball to sing her anthemic dance belter Only Girl.

Wearing a skimpy blue jacket and vertiginous fluorescent platform shoes, the Barbados-born star was uncharacteristically overdressed.

It wasn’t long, however, before Ri Ri stripped into something more comfortable — a bikini which looked like it was made entirely of Skittles.

Racing through her back catalogue of hits at breakneck speed, she sang Disturbia, Shut Up and Drive and Man Down before nipping off stage for one of many costume changes.

Chained and wearing a provocative black leotard, she performed the raunchy S&M, while a legion of leather-clad slaves groped her.

From then on, however, the show began to flag.

Hampered by painfully long breaks for Rihanna to slip into another sex kitten outfit, with little happening on stage inbetween, the show stopped and started like a poorly oiled second hand car.

There was also little thought to the overall concept of the night and the result is a show which failed to flow.

Even the spectacle of the star riding a giant pink cannon and her finale of Umbrella and monster hit We Found Love couldn’t save the show from feeling sluggish and incoherent.

Her fans may still have had a blast, but they deserved better.