[MEXICO-USA] You've got to give Maurice Edu some credit. Faced with the prospect of playing centerback against Mexico's formidable array of attackers in their home fortress, Edu confidently referred to playing in the middle at the 2008 Olympic Games. The fact he's rarely played there since didn't seem to faze him, nor did the possibility of being partnered with Geoff Cameron, whose conversion from midfield to the back line has been encouraging but is still strictly a work-in-progress at the international level. This will be one subplot to the main story when the USA and Mexico meet Wednesday (8 p.m. ET, ESPN2, Univision) for the first friendly on Mexican soil since 1984.

Angst over the aging U.S. back line has overshadowed some other nettlesome problems, such as how to get sufficient offensive impetus through midfield against good teams without sacrificing too much defensive resiliency. If the rugged, talented Edu had the same range and quickness as Ricardo Clark, for example, Klinsmann could deploy the other three (or four) midfielders confident that there was a rock-solid anchor backing them up. But there's not yet anyone in the U.S. player pool who can serve as its Gennaro Gattuso or Patrick Vieira and thus Klinsmann has tweaked his formations and personnel in search of the right balance.

Players of that ilk greatly ease stress on the centerbacks and also serve as vital conduits to the attack. Jermaine Jones can destroy and get forward occasionally but he's foul- and caution-prone. Kyle Beckerman has tremendous heart, great workrate, and good feet ... at the MLS level. In Concacaf he's borderline.

If Edu does start at centerback against Mexico, it's hard to tell whether this is a one-off Klinsmann move out of necessity or if the coach has him far enough down the depth chart at central mid to truly consider him a long-term solution. The age of Carlos Bocanegra (33), the worrying struggles of Oguchi Onyewu, and the limitations of Clarence Goodson have the centerback position of great concern with Brazil 2014 less than two years away. Maybe Tim Ream and Cameron accelerate their development sufficiently in England to fill the void, but with Bolton's relegation Ream's short-term future is one division below the Premier League, and Cameron's coach at Stoke City, Tony Pulis, may try him out in midfield.

The exclusion of Clint Dempsey and Michael Bradley from the Azteca squad significantly weakens it, yet Klinsmann does have six Mexican league products at his disposal. While they are months behind their MLS counterparts in game sharpness -- the Liga MX campaign began 10 days ago --  they do know the Mexican players and have labored in the heat and altitude and smog of Azteca. But a key feature of Mexico's re-ascension over the past two or three years has been the growth of their collective game, to attack and defend as a unit, and to connect passes and swap positions, rather than perform as individuals insistent on showcasing their uniqueness. They won the Gold Cup last year despite losing five players to a tainted drug test, and last week took the Olympic gold medal in the absence of projected linchpin Javier Hernandez, who is in the team that will face the USA.

There are few players as different as Cuauhtemoc Blanco, and at times he gave the Americans migraines with his bunny hops and sombreros. But he and many teammates didn't deal well with frustration and much of the Mexican mindset of the last decade focused on why success against the top European and South American teams -- and not only in Azteca -- didn't translate against the USA. That stigma has been obliterated by recent results, thus removing a critical factor that helped the USA defeat technically superior players. There are certainly gifted Americans --- Landon Donovan, Jose Torres, Joe Corona, Benny Feilhaber, Sacha Kljestan, Dempsey -- but in the Mexico team confidence with the ball is nearly universal.

In one regard, during his year in charge Klinsmann has been plagued by the same absences as predecessor Bob Bradley toward the end of his tenure. Striker Charlie Davies and midfielder Stuart Holden have yet to return to the national team, and while neither is the Ulimate Solution at his position, being deprived of their talents shows how shallow is the water in certain areas of the player pool. One year at the helm, or even two or three, isn't enough time for Klinsmann to change that dynamic.