In which year did Wimbledon start using yellow tennis balls?

The balls used in tennis at Wimbledon are yellow and have been since 1986.

Prior to 1972, tennis was played with white balls when viewers would tune into the sport on black and white TVs. The monocolour pictures meant the white ball was easy to spot against the dark colour of the grass court. But as more and more TV viewers started splashing out on colour sets, sports broadcasters noticed that audiences were having trouble picking out the ball on screen.

So in 1972, it was decided that tennis balls should be switched to a new, brighter, more fluorescent colour. A whole host of colours were trialled in research to see which ones were the most visible on colour TV, including ones that were bright orange and neon pink. But in the end, the study found that the colour 'optic yellow' was the best for TV audiences to pick out.

After the study, the International Tennis Federation ruled that balls could be introduced at tournaments in that colour. But it wasn't until 1986, that the All England Club decided to introduce the optic yellow balls at Wimbledon.