Nicole Kidman and husband Keith Urban caused a stir when they stepped out in matching his-and-hers leather outfits at a Sydney Swans Aussie Rules football game on Saturday.

While it is quite common for some couples to start dressing like each other, the Urbans might be taking it too far.

The strange combo of leather jackets, black baseball caps and dark glasses may well have been chosen to disguise themselves to watch the Sydney Swans play the Fremantle Dockers at Sydney Crickert Ground.

Incognito?: Nicole and Keith debut their 'his and hers' leather look

The Oscar-winning actress, 41, gave birth to daughter Sunday Rose - her first biological child - in Nashville, Tennessee, on July 7.

Kidman, who has two adopted children with Hollywood actor Tom Cruise, shed her baby weight in record time, appearing to be back to her slender self just 10 days after birth.

She reportedly worked out with a trainer for up to five days a week in a bid to avoid gaining excess weight.

New parents Nicole and Keith on their way to a Sydney Swans game

The one-month-old baby's name was inspired by the Australian artist Sidney Nolan's muse Sunday Reed. Rose was the name of Urban's late grandmother.

Unlike other Hollywood mothers such Jennifer Lopez and Angelina Jolie, Kidman and her husband have refused to sell images of their daughter, because they believe it is inappropriate.