Dr Paul Hawkins, the creator of Hawk-Eye, the ball-tracking technology, insisted that his system was accurate last night after controversy in the men’s final at Wimbledon when a vital line call was challenged.

In the third game of the fourth set, with Roger Federer a break down and serving at 30-30, he did not play at a ball near the baseline. He thought that it was out, the line judge thought it was out, the umpire thought it was out and a BBC freeze frame seemed to confirm this, too.

However, after a challenge from Rafael Nadal, Hawk-Eye showed the shot in. Federer lost his temper, declaring that the machine was “killing him” and demanding that it be turned off.

The All England Club has promised to investigate, although Ian Ritchie, the chief executive, added that they had carried out an “exhaustive” series of tests before the tournament, tests that Hawk-Eye had passed.

Hawkins said that the ball had landed in by 1mm. He claimed that the naked eye was deceived because of the way a tennis ball compresses and skids on landing.

“The ball will be in contact with the ground for about 10cm,” he said. “In the very first impact, it will compress so that the bottom half is flat. Then it will start to roll and skid and uncompress. The freeze frame the BBC used showed the ball about 7cm after it touched the ground.” He said tests had showed that his technology was accurate to within 3mm. “The ball was definitely in,” he added.