The Norwegian royal, 50, was spotted at the annual Friendship Football match at Skaugum where she looked unusually casual in an unexpected double denim ensemble.
The Crown Princess wore a pair of mid-wash blue skinny jeans with a light-wash denim shirt which featured a collared neckline and utility pockets across the chest.
Adding a touch of royal elegance to her look was Mette-Marit's hair and makeup looks. Her icy blonde locks were styled in voluminous waves which cascaded over her shoulders and her makeup was kept simple with a radiant complexion and defined eyebrows.
Rounding off the look were her chic Saint Laurent tortoiseshell sunglasses.
The royal has proven she is not afraid of breaking royal fashion rules and opting for a more relaxed look. She was seen earlier this month in jeans and running shoes as she walked around the Ulsrudvann lake in Ostmarka during the official state visit of King Frederik and Queen Mary of Denmark.
The royal was seen rocking an opposing look to the Opening of the Culture Days at Blakstad Hospital in Vettre on 28 May.
The mother-of-three was seen wearing a tasteful linen shirt dress, the 'Frida' from Max Mara, which featured a tied-in waist, button-down-front, and rolled sleeves.
The floaty summer-ready number was teamed with a pair of baby pink suede heels to match her 'Entrelace' clutch from Maria La Rosa and her 'Triomphe S167' sunglasses from Celine.
Mette-Marit's daughter Princess Ingrid wasn't present at the football event on Wednesday but was seen with her mother earlier this month in military uniform from the balcony of the Royal Palace in Oslo, on Norway's National Day.
The 20-year-old royal is a recruit in the Norwegian army having started her 12 months military training at the Engineer Battalion in Brigade Nord in January.
The mother-daughter duo had gotten changed out of their formalwear and into traditional Norwegian dress as they greeted volunteers from the children's parade.
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