Fifteen years since his last outing and only one year since he announced that he was retiring from pop, George Michael, 43, started his 25Live European tour in Barcelona on Saturday. “Here I am/Is it too late to try again?” he sang, shrouded in darkness, as the band played Waiting. The tumultuous welcome he received when he finally stepped into the light suggested that it was not too late at all as far as the 16,000 fans jammed into every corner of the vast arena were concerned.

But while absence makes the heart grow fonder it does little to hone an artist’s performing skills.

Wearing black leather trousers and jacket, Michael paraded across a state-of-the-art stage that was ingeniously lit from within and extended behind him in one seamless sweep, like an electric curtain all the way up to the lighting trusses. With the band tucked away on a three-tiered shelving system at the back — out of sight and out of mind — it was all down to the star of the show to deliver the goods, and, while Michael was clearly relishing the occasion, it took a while for him to find his voice and for the production to find its feet.

There were odd glitches, as when Michael, marooned in the middle of a darkened stage, had to ask someone to start the next track please. And for some unexplained reason Too Funky was played twice. But the besetting problem, particularly during the first half of the show, was an excess of slow, maudlin ballads — Praying for Time, You have been Loved, My Mother had a Brother and others — which cumulatively drained the show of its energy. Even when he sang Faith at the start of the second half, he performed it seated on a stool, while a silhouette of his old self, projected on to the screen at the back, made the hip-shaking moves from the original video.

Michael remains a class act with a dedicated and vociferous following. And when he ended the show with I’m your Man and an encore of Careless Whisper the applause was sustained and deafening. But the pop landscape has changed in his absence, and at times he looked a bit creaky.

When Robbie Williams or Madonna mounts a show of these proportions, it is a fast-moving theatrical song-and-dance feast. The only moment of visual drama in Michael’s set was the arrival during Shoot the Dog of a giant inflatable likeness of George Bush, who looked in surprisingly good spirits when you consider that he had the jaws of a British bulldog clamped on to his crotch. It was a crowd-pleasing moment, but still not much of a song, and simply not enough to rescue a show noticeably lacking the wow factor.

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