These teams might reasonably have been expected to meet in the final of the 2017 CONCACAF U-20 Championship, but the USA's campaign took an unexpected diversion, and an opening-game loss to Panama ultimately cost the Americans the top spot in their group. So the USA enters the Classification Stage as a group-stage runner-up, not winner as had been expected.
Mexico has performed much as anticipated: very well. Three wins in three games, nine goals scored, none conceded: El Tri looks in imposing form. But it also only beat Honduras, the second-best team in its group, 1-0 - and conceded a penalty during that game, which Los Catrachos could not convert.
The USA made light work of its two group-stage Caribbean opponents - Haiti and St. Kitts and Nevis - but struggled against an organized and tenacious Panama. Maybe the team that won its last two group stage games by a combined score of 8-2 is a truer reflection of the USA's ability than the one that couldn't assert itself against 10-man Panama. Maybe not. Mexico will offer a thorough examination of the US U-20s' claim to be one of the better teams in CONCACAF at this level.
Though this game is not the final - and these teams cannot meet in the final - it is arguably more important than that. This stage of the competition will decide CONCACAF's representatives at the 2017 U-20 World Cup. Mexico, the USA, and El Salvador are in a three-team group that will advance two teams to the bigger tournament in South Korea later this year.
With only two games to play to decide who goes to South Korea and who stays home, a strong start to the Classification Stage is important for both sides.