Rachel Riley to be replaced on Countdown by YouTuber

Riley took over as co-host of the show from Carol Vorderman in 2009.

The 39-year-old has been hosting the game show since 2009 when she took over from Carol Vorderman.

YouTube star, Dr Tom Crawford will temporarily take over from Riley as she films a new project.

The social media creator with over 200K YouTube subscribers is more than qualified for the role.

Crawford has a PhD in Fluid Dynamics from the University of Cambridge as well as a maths degree from the University of Oxford.

In a post on Instagram, the mathematician shared that he 'still can't believe this happened', and labelled Riley as 'irreplaceable'.

Countdown has been on TV screens since 1982, with over 8,000 episodes airing since.

Richard Whiteley, Des Lynam, Des O'Connor, Jeff Stelling, Nick Hewer and Anne Robinson all having stints as hosts before Colin Murray took over in 2022.