Football's yellow and red cards go digital in Uruguay trial

Football's familiar yellow and red cards have received a digital makeover in Uruguay, where a referee has tested an electronic alternative during a competitive match.

Referee Eduardo Varela used a smartphone-sized device instead of traditional cards during Thursday's Copa Uruguay match between Nacional and Rentistas, which Nacional won 3-0.

The device has two buttons that turn its screen yellow or red, allowing referees to display cautions and dismissals while recording disciplinary decisions electronically.

Rentistas player Juan Pablo Plada became the first player to receive a digital yellow card when Varela booked him in the 12th minute.

Developed by private company REFe, the technology is designed to reduce paperwork by digitally recording disciplinary decisions, substitutions and other match incidents.

The developers hope to eventually link the information to the Uruguayan Football Association's match-management system.

But visibility remains a problem. An earlier trial was abandoned because sunlight made the screen difficult to see, while spectators and television viewers also struggled to distinguish the colours during Thursday's match.

Developers are considering adding LED lighting to improve visibility.

The technology remains experimental, although its creators hope it will eventually be adopted by South American football's governing body CONMEBOL and FIFA.