The 37-year-old singer suffered a major wardrobe malfunction when he split his trousers while performing his solo section.
Brushing off the accident, he told the sell-out crowd at Cardiff's Millennium Stadium, 'I'm so excited I've split my kecks.'
The TV screens then zoomed in on the tear in his crotch while Robbie urged anyone with a camera to post videos of it on his website.
Ever the professional, he talked about abandoning his slot but then decided to soldier on in his ruined trousers before ripping them off completely after singing Angeles.
Take That fan and witness Natalie Murray, from south Wales, told the Metro newspaper, 'No one might have noticed at first, but Robbie seemed to want to make a big deal of it.
'After all these years he still wants to be the centre of attention. He wasn't embarrassed at all.'