Sebastian Widmann

As Germany coach Joachim Low prepares for the 2014 World Cup in Brazil, he faces familiar problems to overcome. Ever since he took the helm as "Bundestrainer" in 2006, the Schonau native has regularly shuffled his defense, rotating center-backs and full-backs again and again, and even experimenting with three-man back lines on occasion.

Low has an abundance of depth especially in attacking midfield, but his options along the back four are few, and even fewer inspire much confidence that they will be reliable throughout the tournament in Brazil.

If there is one defender Germany can count on to deliver in Brazil, it's right-back Philipp Lahm. As captain of his country and treble-winning club Bayern Munich, the 105-time capped Germany international is immensely experienced.

He is, at 30 years of age, still in the prime of his footballing career. And although his mistake contributed to Germany being eliminated from Euro 2012, he has performed again and again on a big stage in competitions before and since.

Lahm has often been used in midfield at Bayern this season, but his natural and best position is on the right of defense. And there is a lack of proven options behind him, with natural center-backs Benedikt Howedes and Jerome Boateng, as well as defensive midfielder Lars Bender as alternatives. Converted right-back Kevin Grosskreutz is perhaps the most likely deputy for Lahm, but the Dortmund man lacks international experience and surely will only start if Low finds himself severely short of options in central midfield.

The interior of defense is a more contended area, with Per Mertesacker, Jerome Boateng and Mats Hummels the primary contestants for just two spots in Low's team. Every combination of the three has been tried extensively since Euro 2012, although Boateng has started all seven of Germany's competitive and friendly fixtures since last September. In this time Mertesacker has started five matches, Hummels two, although the latter's appearances both came in the last four fixtures.

Matthias Schrader

Boateng at this point seems a lock for Low, his presence in a treble-winning Bayern defense being the most compellingly decisive factor.

Mertesacker has experience on his side, the 29-year-old having earned 96 caps and started at every major international competition since 2006, barring Euro 2012, which came shortly after he'd recovered from a nasty ankle injury. He reads the game exceptionally well, is indomitable in the air and rarely has to go to ground to win the ball.

Hummels' advantage is that he is with little doubt the most talented all-round defender Germany have. His anticipation borders on the prophetic, he reads the game impeccably, is equally adept in defending on the ground and in the air and has superlative ball skills. And although he is remembered for a mistake against Italy—something for which Lahm is not remembered—Hummels was, along with eventual winner Andres Iniesta, a top candidate for the Best Player award at Euro 2012.

In previous years, Mertesacker's experience may have been a trump card in his favor. But at 25, Hummels has finally entered the prime of his career. Center-backs are rarely developed until their mid-20s: For example, Nemanja Vidic was nearly 26 before he became a starter at Manchester United, and Thiago Silva failed at Porto and Dynamo Moscow before becoming a top defender at Milan at the age of 25.

No longer a rising talent, Hummels has played admirably in the last two Champions League campaigns for Dortmund, during which he has amassed almost twice (seven) as many knockout-round appearances as Mertesacker (four) has in the duration of his career. Although he's made judgmental mistakes in the past, his maturity and experience can and will naturally reduce the rate of such errors. The proof is in his record: Although injured several times this season, he's been consistently spectacular at the back for BVB, especially this spring.

This season has generally been positive for Mertesacker as well, but it also has shown his weaknesses. Arsenal conceded 20 goals in away matches to Liverpool, Chelsea, Manchester City and Everton, the other members of England's top five.

In each instance, the Gunners' main problem was being caught on the counterattack, their lack of any discernible holding midfielder leaving large gaps between the midfield and defense. This allowed opponents to run at Mertesacker, exposing his weaknesses: a lack of pace and one-on-one defending ability.

Given that Sami Khedira's form and fitness ahead of the World Cup is in doubt and considering that Low may use the defensively limited Toni Kroos in a holding role to accommodate his many attacking midfield options, Germany may have the same weaknesses as Arsenal. In that case, Hummels is a better fit than Mertesacker. But Low may have his own ideas; he historically has been loyal to his longstanding favorites, among whom the Arsenal man is certainly included.

Left-back is another position that is well-contested, but not due to a surplus of options. It is perhaps Germany's weakest point; the fact that Jurgen Klopp (in a recent press conference, via Goal.com) and Lothar Matthaus (via Bild) have endorsed Erik Durm, a forward until this season and currently a backup at BVB, to be part of Low's World Cup squad is—despite the player's strong recent form—quite revealing.

Low's option are few. Dennis Aogo will miss the World Cup due to an ACL injury, and Marcell Jansen has never played in the Champions League and could be relegated with Hamburg this May. Marcel Schmelzer appears to be Low's first choice if not for any other reason than that he is a reliable, if unspectacular, role-player at a top Bundesliga club that is regularly competitive in the Champions League. The same cannot be said for any other option.

Schmelzer's long-term status at Dortmund and for Germany may be uncertain, especially with the meteoric rise of Durm and potential development of academy players. But with Germany's first World Cup match less than two months away, it would be an enormous surprise to see Low look past him. Not yet, anyway.

Consistency in defense has not been a huge priority for Low in the past, and he could well shake things up between now and the beginning of the World Cup. In central defense he certainly has options, and on the right there a few choices if he decides to use Lahm in midfield.

Anything can happen in the coming weeks, though, from injuries to drastic swings in form. It's not yet certain who Low will choose, but for now a back four of Lahm, Boateng, Hummels and Schmelzer looks just about right.

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