ABC newsreader's hilarious reaction to being caught 'daydreaming' on-air

There's a lesson in this for television presenters everywhere.

If the camera is pointed at you, don't let down your guard. Not even for a moment.

ABC News 24 presenter Natasha Exelby learnt that the hard way after a clip of her 'daydreaming' on the job went viral over the weekend.

After a story from Queensland wrapped up over the weekend, the camera cut to Exelby fiddling with her pen. Her reaction after realising the cameras were rolling, however, was what really got tongues wagging.

After an audible gasp, the experienced television presenter quickly finds her feet.

"Now to sport with Meredith Sheehan," she said, throwing to the next television package.

The quick save didn't stop bemused viewers going to town, though.

But fellow journalists did leap to her defence. After all, we've all had our tough days at the office - it just so happens that for some of us, our bad days are broadcast to thousands of people all over the country.