Very rarely can a single day of qualifying for one team, or this case teams, be so important to one national team.
But the United States senior men's team and the U-23 Olympic team playing on the same day is a rare occurrence. The senior team can gain control of their World Cup qualifying group with a road win at Guatemala and the Olympic team plays the first leg of a playoff against Colombia (5pm, FS1).
While I won't focus on the Olympic team here, check out this post from Stars and Stripes FC, today is a very big day for the USA's soccer program as a whole.