Grimmy swapped one teen pop sensation for another yesterday as he lined Biebs up as the latest to join his gang.
The new Radio 1 breakfast show host interviewed Justin yesterday and posted this picture of the two of them "getting swaggy" on Twitter.
Harry obviously isn't the jealous type though as he still turned up to support his BFF as he hosted his last night time show on Radio 1.
Grimmy is due to take over the early slot from Chris Moyles on 24 September, with Chris hosting his last show tomorrow.
Hazza and Grims then hit the town with a bunch of their trendy pals including Pixie Geldof and designer Henry Holland.
There was no sign of Bieber though so perhaps it is all over for him and Grimmy before it really even began.
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