And his choice of a traditionally slimming black suit and T-shirt failed miserably to hide his expanding waistband.
Earlier today George disappointed fans when he pulled out of tonight's gig - the second in a run of four concerts at the famous venue - due to illness.
The 48-year-old star has been plagued by problems over recent years.
His drug use lead to several arrests, car prangs and even a jail sentence.
In December 2009, he claimed he was addicted to cannabis and said that he used to smoke 25 joints a day.
And in July 2010, he was arrested and charged with possession of the drug and driving under the influence of drink or drugs after his car smashed into a branch of Snappy Snaps in Hampstead, London.
He was sentenced to eight weeks in jail and released in October 2010 after serving four weeks at Highpoint Prison in Suffolk.
George kicked off the Symphonica tour in Prague, Czech Republic in August and revealed he had split with long-term love Kenny Goss two years ago.
And last night, on the first night of the British leg of the tour, he performed a string of cover versions, including Rihanna's Russian Roulette, The Police hit Roxanne and Amy Winehouse's Love Is A Losing Game.
He was, backed by a 41-piece orchestra throughout.
In fine form... George MichaelXPOSUREPHOTOS.COM
He introduced his version of New Order's True Faith with a dig at his own troubles, saying: "This is a song about the nature of addiction which, of course, I know nothing about."
He also treated fans to a string of his own songs, such as Cowboys and Angels, A Different Corner and You Have Been Loved.
And he finished with a medley of three hits ? Amazing, Freedom and I'm Your Man.
Or should that be I'm Your Flan?