Alex Morgan headed in the game-winning goal in extra time to lift the United States women's soccer team to a 4-3 victory over Canada and into the gold-medal game at London Olympics.

The USA advanced to its fifth straight gold-medal game with a chance to avenge its 2011 World Cup finals loss to Japan via penalty shootout. Earlier, Japan defeated France, 2-1, in the other semifinal.

The Americans and Japanese will fight it out for the gold at Wembley Stadium in London. The Canadians, who haven't beaten the US since 2001, play France for bronze.

The Americans are vying for their fourth Olympic gold medal and third in a row. They struck gold in 1996, 2004 and 2008 and silver in 2000.

With the game tied at 3, Morgan scored on a 6-yard header from a long cross by Heather O'Reilly in the 123rd minute to complete the Americans' comeback from a 3-2 deficit.

Abby Wambach tied the game at 3 with a goal in the 80th minute while Megan Rapinoe scored in the 54th and 70th minutes for the Americans, who overcame a hat trick by Christine Sinclair, who scored in the 22nd, 67th and 73rd minutes.

Sinclair scored the first of her three goals in the 22nd minute and gave the Canadians a 1-0 lead that they would keep in the first 45 minutes of the game.

Rapinoe got her side back into it after the break when she fired in a low hard corner on goal that found its way through Canada's defense to tie the game at 1-1.

Sinclair got her second score from a header in the 68th minute before Rapinoe countered with a brace of her own from a rocket shot in the 70th minute.

Three minutes later, Sinclair netted another headed goal to complete her historic hat trick but Wambach converted a penalty kick to tie the score.