His horde of female fans went gaga after her unveiled his beefy new look on Twitter just a day ago.
But Justin Bieber chose to cover up his bulging biceps and glistening pectorals under a heavy black jacket as he went walkabout in New York on Tuesday.
Bizarrely the 18-year-old wore a disappointed look on his face despite the he was arriving to rehearse ahead of an appearance at a Victoria's Secret fashion show in Manhattan.
The teen idol was certainly in a black mood, as his whole ensemble was that colour, save his baseball cap which bore the word 'dope' in white lettering.
Perhaps the Baby favourite was sad because he was separated from his puppy love Selena Gomez, who was busy regaling her fans with tales of winning the Glamour Woman of the Year award on Twitter.
However the fact saucy model Lily Aldridge, who is married to Kings of Leon star Caleb Followill, has been singing his praises will surely have perked him up.
She tweeted: 'Can't wait to see Rihanna, Bruno Mars and Justin Bieber tomorrow night at the Victorias Secret VS Fashion Show!'
Justin took great delight in posting an image of his new look action man physique on Twitter on Monday.
He sucked in his stomach and flexed his muscles while he took a picture of himself posing in front of a mirror on his mobile phone, with a cheeky friend getting in on the act by standing to his rear.
Along with the photo Justin tweeted: 'Me and @nickdemoura dance rehearsal get ready #watchout'
It was certainly popular with his followers, with one even saying: 'Why do you do this to us! Proper teasing us.'
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