It was the grand finale of this series of Ant & Dec's Saturday Night Takeaway - something was bound to go wrong.

And it was during the deciding leg of Ant versus Dec that it all went a bit wrong for one half of the duo.

Each week the pair have gone head-to-head in a series of challenges in the hope they will be crowned the series winner.

Tonight saw the boys head of in go-karts powered by a variety of different power tools and Stephen Mulhern dressed as a giant yellow drill.

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After the first couple of challenges, Dec had taken a convincing lead.

As the pair headed over to their next DIY karts, Ant tripped over Dec and rolled commando style across the track.

You can see the action in this Tweet from the show.

The loser of Ant versus Dec must face a forfeit - this year's was particularly brutal as the loser must publicly applaud the other, for the next 12 months.

It was Dec who was victorious despite Ant gaining the lead at one point so will be showered with paise for the next year.

Ant got started straight away with this post to social media.

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:: If you missed the final episode of Ant & Dec’s Saturday Night Takeaway series 18, you can catch up with the show via ITV Hub.