Canadian head coach John Herdman is already stirring the pot.
Herdman claims the U.S. Women's National Team uses "highly illegal tactics" on set pieces. He is drawing attention to the physical play of the USA. And that is odd. Why? Because Canada is just as physical as the USWNT.
What Herdman is most likely trying to do is have the referees looking at the action more closely in an attempt to limit the United States' physical advantages. If he gets one extra call because of his statements then they succeeded.
With or without his statements, the match between the USWNT and Canada is going to be good. Two of the best goal scorers in women's soccer history are on the pitch, alongside numerous up and comers.
Here are five players you need to watch today.
Melissa Tancredi has been one of the breakout stars of the Olympic soccer tournament.
With the focus on Christine Sinclair, Tancredi has sent four balls into the back of the net. She is tied for the tournament lead with USA's Abby Wambach.
With a second premier striker for Canada rearing her head, the U.S. will need to play fantastic defense to keep their scoreless streak going.
Look for Tancredi to have several chances in this match.
Lauren Cheney has been flying under the radar in the Olympic Games. It is unusual for her to be so quiet.
Cheney will not be kept silent for long, and she will soon come alive. No better time than the Olympic semifinals to do so.
While she has helped the midfield with possession, it has been every other midfielder helping out in the offensive department. Carli Lloyd has a pair of goals, Megan Rapinoe has been sensational sending in crosses and others have come in to play their roles as well.
If Cheney's quiet Olympics causes Canada to have a memory lapse on how good she is, it will make for some exciting results.
It is time for Cheney to reassert herself.
I have fallen in love with what Kelley O'Hara has brought to the USA's backline.
She has been a quality defender, but it is everything else that is a big step in the right direction from where the defense was in the World Cup.
The Americans have tightened the defense up in London.
O'hara has come up the field to assist the offense, but shown the speed to recover when a counter begins.
When she helps the attack, the opposing defense needs to worry. O'Hara is an offensive player at heart. Her talents have added something new to the U.S. backline and it is a welcome sight.
140 international goals. That pretty much says it all.
Christine Sinclair is dangerous.
Having already listed Tancredi as a player to watch, I wanted to look toward the defense or midfield for the next Canadian, but it is impossible to ignore Sinclair.
Along with Tancredi, the USWNT defense has their hands full. They are very physical forwards.
With Canada's two dynamic forwards, possession becomes vital in this match. The U.S. has to keep the ball away from them as much as possible.
Alex Morgan's electrifying goal scoring began back at the World Cup and has continued on through 2012. She showcased it in the opening match against France to help the U.S. overcome a 2-0 deficit and win 4-2.
However, it has been her other tools that have shined brighter during the Olympics.
Quality defending, ball control and excellent passes have shown she is more than just a scorer but an all-around beast on the pitch.
Morgan is great on the ball and has fantastic vision. More often than not, she makes the right play and the end result is a USWNT goal.
Against New Zealand, Morgan had her most lackluster performance of the tournament. That still did not stop her from being the player who created the first goal of the match. She played a perfect pass between a defender and the keeper to Wambach, who put it in. And that was her quiet performance.
Morgan's exciting play makes her a must watch.