Nations League preview: How U.S., Mexico, Canada, Panama stack up

After several weeks of competition, the CONCACAF Nations League has locked down its semifinal stage: the U.S. vs. Mexico and Panama vs. Canada. 

The victors of those semis will face one another to determine who is best in an increasingly competitive region.

But how did these teams qualify from the field of 41 competitors, and what have we learned from their journeys? Here's a breakdown of the remaining teams:

United States:  The Americans have few complaints coming out of the group stages, finishing as the top seed in North America with three wins, a draw and a +12 goal differential from their four recent games. 

Captain and midfield maestro Tyler Adams sat out injured for two of those four games, and Luca de la Torre stepped up in a big way to fill his cleats. 

While the team still hasn't found a starting striker, Daryl Dike and Alex Zendejas look up for the challenge. The U.S. is in excellent shape following its disappointing but unsurprising Round of 16 exit at the World Cup.

Mexico:  El Tri, the jewel of the CONCACAF crown, struggled mightily in its Nations League games, qualifying as the final seed. Their biggest problem? Shot conversion. 

In their final game against Jamaica, el Tri had 25 shots, with just four on target and two resulting in goals. (One came on a penalty.) That's a woeful shot-to-goal ratio from a team that has long prided itself on attacking precision. 

With Canada and El Salvador rising in the CONCACAF ranks and Costa Rica and Panama always capable of getting a result, Mexico may be glancing over its shoulders. It isn't the undisputed kings of the region anymore.

Panama: The Panamanians were the biggest shock of the Nations League group stages, cruising into the second seed on the back of several inspired victories. 

We've seen Panama excel before — it qualified for the 2018 World Cup at the deserved expense of the U.S. — but the precision and coolness of its semifinal qualification merits praise.

Panama is excellent at tricking the opposition into mistakes. But while counterattacking implies plodding, defensive play, the Panamanians aren't hesitant to take the game to their competitors when it makes sense. 

They're a title contender, especially considering their opponent is Canada — a team they beat resoundingly last year.

Canada: It's been a wild two years for Canada, which has gone from North American also-rans to genuine trophy contenders.

The Canadians qualified third after thumping Curacao and Honduras, but it wasn't all smiles in the Canadian camp. Boardroom drama over paychecks led to lack of focus in the early stages, and it is the  the only semifinal competitor that lost a game in the group stages. Canada hopes to change that narrative in the semis. 

With Alphonso Davies tearing up the Champions League with Bayern Munich and Jonathan David slamming in goals for Lille, Canada's biggest threats are speed and physicality. It is lighting quick on the counter and refuses to be intimidated by opposition tactics.

The CONCACAF Nations League semifinals kickoff in Las Vegas on June 15.