She had spoken of “redemption” for missing a penalty in the shoot-out of the World Cup final against Japan a year ago and Carli Lloyd, the 30 year-old United States midfielder, left nothing to chance in achieving it tonight.
Having headed the first goal early on, she drove in the second from 20 yards and continued to play her part as Japan fought back superbly in a compelling final watched by a women's Olympic record crowd of 80,203.
In the end, however, there was no keeping the Americans from winning their fourth gold medal out of the five Olympic tournaments since women's football was introduced in 1996.
Some three inches smaller on average, Japan declined to be inhibited, kept playing their neat passing football and did not deserve to be even one goal behind at the interval. After Lloyd's double, Yuki Omigi halved the deficit but the best chance to equalise disappeared seven minutes from the end when Hope Solo in goal kept out the young substitute Mana Iwabuchi.
The Americans' coach Pia Sundhage promised that her team would add to their total of 14 goals in the previous five games and they had done so after only eight minutes. A well worked effort it was too, as Tobin Heath crossed low to Alex Morgan, whose chip to the far post found two attackers homing in. Abby Wambach, seeking a sixth goal in as many matches, swung her left foot but was beaten to the draw by Lloyd, arriving from midfield to head in.
Twice before half-time the crossbar kept the Japanese out. First, Solo did well to push Ogimi's header onto the frame of the goal and later the same player struck the bar with a fine drive. Shinobu Ohno curled an equally good effort just wide and Japan should have been given a penalty when Heath handled a free-kick.
Eight minutes into the second half, they fell further behind as Lloyd was sent away by Megan Rapinoe to score what would eventually prove the decisive goal; but only after the Americans had been pushed all the way to the podium.
Earlier Canada beat France 1-0 to take the bronze medal, which they were presented with at Wembley after rushing down from the City of Coventry Stadium.
Japan: Fukumoto; Kinga, Iwashimizu, Kumagai, Sameshima; Miyama, Sakaguchi, Sawa, Kawasumi; Ogimi, Ohno.
USA: Solo; Peilbet, Rampone, Buehler, O’Hara; Rapinoe, Boxx, Lloyd, Heath; Morgan, Wambach.
Referee: B Steinhaus (Germany)