The midfielder grabbed her country's winning goal in extra-time in
It was a moment of personal redemption for Lloyd, who had missed a penalty in last year's World Cup final defeat against the same opponent.
A predatory header and a wonderful curling effort made her the star attraction this time, but 30-year-old Lloyd was quick to appreciate the wider importance of the game.
The official attendance totalled 80,203 - smashing the previous Olympic record for women's football, which was set at 76,481 in Atlanta 16 years ago.
"This is pretty crazy. To have 80,000 people for a women's final is unbelievable," she said.
"It says a lot about the growth of women's soccer and we feel very lucky. Wembley was amazing...to play in all these historic stadia is amazing.
"I don't know how many were in
He was handed a central role in the medal ceremony at full-time and found himself treated to a loud chorus of boos from around the ground - something that was not going to overshadow Lloyd's match-winning turn, though.
Reflecting on her own efforts, she said: "I really seized the moment. As a soccer player you don't know how many shots you'll get at an Olympics and I came up big today. I wanted to prove I am a special player.
"Back in Beijing I scored the only goal against
"Maybe for my third Olympic final I'm going to have to score a hat-trick. I want to keep training and keep working hard because I want a World Cup and a third gold medal."
Lloyd insisted her spot-kick blunder in the World Cup final did not play on her mind, insisting her side was fully focussed on reasserting its dominance in a competition where it has now claimed Olympic gold four times from five attempts.
"The penalty shot wasn't in my mind one bit. Those things happen," she said.
"This was just another game - even though we lost to them in the World Cup - this was just another opportunity to to prove we are the best team in the world and go out to get gold."
USA coach Pia Sundhage paid tribute to the way her side dealt with a lively Japanese side, which reduced arrears through
Japan also hit the woodwork as it forced its opponent back but the reigning champion held on.
"A lot of credit to
"This is not the way we wanted to play but this is the way we were forced to play. They found a way to win, phenomenal.
"They played with a huge heart and they changed the tactics and little bit."
"The players all played very well," said Sasaki.
"Their goal was to win the medal and be the Olympic champions, but having said that, they played very well and I'm very proud of them."
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