Do you want fries with that? Club's unique shirt numbers cause a stir

With the 2019 Chilean league season kicking off over the weekend, O'Higgins were able to debut their mouthwatering new away kit.

While the pink shirt itself immediately caught the eye, the numbers on the back caused something of a stir among fans.

As part of O'Higgins' sponsorship deal with McDonald's, the numbers on the back have been designed to look like french fries dipped in ketchup.

Corporate shill, and almost entirely illegible from a distance of more than a few feet away? The perfect combination.

Back in 2017, Brazilian side Flu de Feira came up with a novel way to advertise deals at a local supermarket chain by taking to the pitch with various price offers on their backs.

For instance, striker Fernando Sobral, who usually sports the No.10 shirt, instead wore the No. 10.98 shirt to advertise a deal on pizza.

Elsewhere, the Romanian national team once swapped their standard squad numbers with mathematical equations to help promote a numeracy campaign among schoolchildren.

As an example, rather than his No.13 jersey, striker Claudiu Keseru wore the "6 x 5 - 4, all divided by 2" shirt for the occasion.

The campaign was backed by Razvan Burleanu, the president of the Romanian Football Federation, who wanted to introduce kids to maths using an "attractive approach."