'Everybody warmed to George Michael' - manager on life with the singer

"Sex, beauty, sadness: All those things resonated with George."

David Austin is casting his eye over George Michael's art collection, which is on display at Christie's in London before going under the hammer on Thursday.

Among the 200 exhibits are a colour-changing portrait of the star by Michael Craig-Martin, a dove preserved in formaldehyde by Damien Hirst, and a life-size bronze gorilla by Angus Fairhurst, which used to live in Michael's garden.

Austin, who rarely gives interviews, was Michael's childhood friend, songwriting partner and manager.

He worked closely with the star's team to put the exhibition together, drawing on the times he'd accompany Michael to buy new works of art.

"I remember going down to the White Cube [gallery] one evening," he recalls. "It was closed when we got there and we saw Damien Hirst's Saint Sebastian through the locked doors.

"I remember his disappointment at not being able to see it - but I also remember him buying it. It's such an imposing piece."

The seven-tonne work restages the death of Christian martyr Saint Sebastian - traditionally depicted as a handsome young man pierced with arrows - using a bull encased in formaldehyde.

Over time, the saint has become a gay icon (more through iconography than biography) and his quiet suffering resonated with Michael.

The star was frequently drawn to mournful pieces, and the Christie's sale includes a haunting cast iron human sculpture by Antony Gormley, a pink coffin by Sarah Lucas, and an unsettling collage of broken mirrors and eyeballs by Jim Lambie.

But Michael also had a love of life and a cheeky sense of humour, exemplified by the triptych Urinal and Sex and Handcuffs, a reference to the star's 1998 arrest for engaging in a sexual act in a public toilet.

"There's a humour about the art," agrees Austin.

"In actual fact, there's a quote of George's that we use in the exhibition where he sums it all up: 'I guess I'm just not afraid of being laughed at.'"

Austin accompanied Michael throughout his career, playing in his first band The Executive and joining Wham! for their Top of the Pops debut in 1982.

After a brief attempt at his own pop career, he co-wrote songs including I Want Your Sex and You Have Been Loved, and latterly became the star's manager, "although I hate that word because George really managed himself".

The art sale is the first public project since the star died as a result of heart and liver disease on Christmas Day 2016, aged 53.

"It does feel very personal walking around it, because George was such a private person," says Austin.

All the money raised will go to charity, continuing the philanthropic work he started in his lifetime.

After his death, it emerged that Michael had worked anonymously at a homeless shelter and donated millions to Childline - including the royalties from Jesus to a Child.

"He was a wonderful person," says Austin. "A caring, kind, giving man.

"It never stops amazing me how he touched people and how much love there is for him."

He remembers Michael's final months fondly. They would spend the days working on a documentary before retiring to Michael's home in Goring-on-Thames to play records or going out for dinner.

"I remember sitting in a restaurant one evening and people were looking across thinking, 'Ooh, it's George Michael!'" he recalls.

"I got up to go to the toilet, and when I came back he was having a cup of tea with two women at the next table. They were just talking about life and their problems, and I was like, 'What is going on here?'

"That was a small moment, but it was important - because that's exactly who he was. Everybody warmed to him, from Princess Diana to those two women in the restaurant."

After Michael died, Austin found himself unable to listen to his music until his phone accidentally started playing a live version of Praying For Time.

"I was in shock. I fumbled with it and I wanted to turn it off," he says. "But then I stopped, and I listened to him and I thought, God, he really can sing can't he?

"George and I worked our whole lives together - but when you're in the eye of the storm, you don't always see it."

Today, Austin is a custodian of the star's legacy and says fans have a lot to look forward to.

"I'm going to make sure all of George's stuff is back out on vinyl," he says, noting that the Older album, which the star called "his greatest moment", is currently out of print.

This December will also see the release of a film, Last Christmas, featuring nine of the musician's most famous songs.

Starring Game of Thrones' Emilia Clarke and Crazy Rich Asians actor Henry Golding, the rom-com has been written by Emma Thompson and is directed by Paul Feig (Bridesmaids, Ghostbusters).

"I did the deal with Emma Thompson because I knew it would be a family film, I knew it would have absolutely massive reach, and we'd be rolling out year after year to a new demographic that would be listening to his music," says Austin.

"It's really taking a note out of George's book. He hated going around selling his wares and this film will do that job."

Austin denies rumours of an all-star tribute concert but says there are other, secret projects in the works.

"There will be lots more happening in the future. Beautiful and significant stuff, too," he says.

"My job is just to make sure everybody hears that music and his legacy continues."

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