Goal-Line Technology

At the 2010 World Cup, England's Frank Lampard struck a shot against Germany that hit the crossbar and landed clearly over the line — by about a foot — before spinning back into play. The goal wasn't given. England, already down, went on to lose 4-1. It was almost a replay of a much older doubt: England's second goal in the 1966 World Cup final, scored by Geoff Hurst off the underside of the crossbar, had been argued over for 44 years by the time Lampard's effort was wrongly ruled out.

FIFA president Sepp Blatter had long opposed goal-line technology on principle, preferring to preserve football's reliance on human judgment and the universal simplicity of the game. Lampard's disallowed goal reversed his position. IFAB formally approved goal-line technology on 5 July 2012, with a certification process to control the quality of competing systems.

The technology reached a FIFA tournament for the first time at the 2013 Confederations Cup, using a camera-based system called GoalControl, which correctly tracked all 68 goals scored that tournament. It made its World Cup debut in Brazil in 2014. Unlike almost everything else in this history, goal-line technology settled a genuinely simple, binary, factual question — did the ball fully cross the line — and largely ended the argument. It remains one of the clearest examples in the sport of technology solving exactly the kind of problem it's suited to.