Rachel Riley suffers wardrobe malfunction as she goes BRALESS for Countdown

It’s an 18-month old clip but viewers are suddenly going nuts for Rachel Riley after realising she went X-rated for an episode of Countdown – and all before the watershed.

The 31-year-old was sporting a hint of nipple after opting to go braless in a tight-fitting pink dress in a throwback clip of the Channel 4 letters and numbers game show.

After eagle-eyed viewers spotted her wardrobe malfunction, the 2015 clip has since gone viral racking up over 300,000 views on YouTube.

We’re not sure Rachel will have an equation to stop this from being a hit.

But her peek-a-boob is not the only thing that has no doubt made the maths whizz blush recently.

Only last week, her boyfriend, Pasha Kovalev, who was sitting in Dictionary Corner with expert Susie Dent, left her red in the face after spelling out the word ‘Phallus’, a term for a penis.

Adding to her embarrassment was the fact she had to spell out the word and stand next to it – much to the amusement of the cast.

But it seems Rachel saw the funny side after all, as she later uploaded a picture of the awkward moment on Twitter, declaring it a ‘fun week’ with her boyfriend.

No doubt all eyes will be on Rachel’s next Countdown outfit…