Both sides won penalty shootouts in the quarter-finals to reach this stage.
For the four-time World Cup winners and four-time Olympics champions, reaching the semi-finals of major competitions has become second nature to USA.
However, they failed to reach the final four in Brazil five years ago, so have clearly been highly motivated to put that right and win the tournament for a fifth time in only seven appearances.
After squeaking through the group stage with four points from three matches, USA faced a tricky quarter-final tie against the free scoring Netherlands Women on Friday.
Indeed, the Oranje had scored a phenomenal 21 goals in three group games to pip Brazil to top spot in Group F, and head coach Vlatko Andonovski must have been fearing the worst when Vivianne Miedema bagged her ninth goal of the competition to open the scoring in the 18th minute.
Miedema had other ideas, though, bagging her 10th of the tournament to enforce extra time and penalties. Unfortunately, the 25-year-old missed her side's opening penalty, with USA converting all four to set up an intriguing semi-final against Canada.
Canada, meanwhile, are set to compete in their third successive Olympics semi-final, but they will be hoping for even better than the bronze medals they won in 2012 and 2016.
It was fierce rivals USA who edged them out in London in 2012, of course, after a thrilling tie ended 4-3 after extra time.
Bev Priestman, who took over as head coach of Canada last year after a decent spell with England Under-17s, will be confident that her squad's mentality is growing stronger all the time, as evidenced by Friday's surprise penalty shootout victory over Brazil after a goalless affair.
Scoring goals has been a slight problem for Priestman's disciplined side, with four goals for and three against in their four matches suggesting that they will look to hit their forthcoming opponents on the break as often as possible on Monday.
Alex Morgan's controversial injury-time strike separated the two sides in the 2012 semi-final, but the legendary forward is no longer an automatic pick under Andonovski.
However, we expect them to start here given their experience and undoubted quality.
Canada, meanwhile, have less competition for places, meaning Priestman is likely to select an unchanged XI.
Thirty-eight-year-old Christine Sinclair earned her 302nd cap against Brazil on Friday, and she will be desperate to add to her phenomenal goalscoring tally of 187 in order to help her country win their first ever major trophy.
USA Women possible starting lineup:
Naeher; O'Hara, Dahlkemper, Sauerbrunn, Dunn; Horan, Ertz, Mewis; Williams, Morgan, Rapinoe
Canada Women possible starting lineup:
Labbe; Lawrence, Gilles, Buchanan, Chapmann; Scott, Fleming, Quinn; Sinclair; Beckie, Prince
We say: USA Women 2-0 Canada Women
We expect USA to be too strong for their neighbouring rivals on Monday, with their attacking firepower and depth undoubtedly superior.
Canada are disciplined but have struggled to score goals against weaker sides than USA so far this summer, so they could be in store for a third successive bronze medal, which would be no mean feat.
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