Germany's CL quartet

Bayern Munich

The reigning Champions League winners go into their home clash against CSKA Moscow on the backs of a routine win. Bastian Schweinsteiger is back from injury, but the Bavarians will still have to do without Javier Martinez and Thiago Alcantara.

Coming off their nearly perfect treble-winning season, Bayern's euphoria has begun to wane somewhat. Saturday's 2-0 victory over Hanover – a team that usually rolls over and plays dead as soon as the team bus passes Munich city limits– was typical of the 2013-14 squad thus far. Pep Guardiola's men dominated possession but took a long while before breaking the ice, whereupon they did enough to secure a comfortable win but no more.

Just another day at the office, you'd think, but Director of Sports Matthias Sammer, whose job is to have regular eruptions, blew his stack, saying the players needed to step to the forefront instead of relaxing comfortably in the shadow of their star coach.

Sammer's contention seemed a bit bizarre, but Bayern will need to up their game, if they're to defend club football's premier title – surely their top priority this season. Fortunately for Guardiola's men, they can use their group D matches to work out the kinks.

CSKA at home is a soluble challenge, Viktoria Plzen should be little more than a sparring partner, and the toughest group rival Manchester City have yet to prove they can produce internationally. It would be a major shock if the defending champs stumbled at the group stage. And until someone knocks them off their perch, they're the top team in the world.

A word of warning to Bavaria, though, no team has successfully defended the Champions League since the competition took on its current name - although AC Milan did manage to retain the competition's predecessor, the European Cup, in 1990.

Borussia Dortmund

As international fans discovered last season, Dortmund coach Jürgen Klopp has a way with words, and his remarks about what is probably the toughest group, Group F, were revealing.

Somewhat freely translated, Klopp told reporters, "Arsenal reached down into the lottery bag and came out with a pile of poo." Klopp was referring to the London club drawing Napoli, Olympique Marseille and Borussia Dortmund, probably the strongest team in pot three out of four. UEFA's seeding system is often subject to criticism, with many in Germany asking how Dortmund could be classified as a "bottom half" team among this year's qualifiers.

Under other circumstances Klopp's "concern" for the North London giants might smack of megalomania, but Dortmund are reigning Champions League runners-up and are off to a perfect start in the Bundesliga. They travel to Italy on Wednesday, and their opponents may find the tape of Dortmund's 6-2 thrashing of Hamburg this weekend uncomfortable viewing.

Dortmund will have to tighten up their defense and in particular get better performances from center backs Mats Hummels and Neven Subotic. But for many people they're the true favorites in this group of death. If they finish first, they look well-poised to make a deep run in the competition.

Bayer Leverkusen

Once a club known for its ups and downs, Bayer Leverkusen are now the model of consistency. Last year's third-place Bundesliga finisher currently sits third in the table, a cut below Bayern and Dortmund but clearly better than the rest in Germany.

The big question is: is third-best enough for coach Sami Hyypia's men to handle Manchester United at Old Trafford on Tuesday? Leverkusen got a 3-1 win over Wolfsburg on Saturday, but facing Robin van Persie and Wayne Rooney is a bit more daunting than lining up against Ivica Olic. Nor are Leverkusen's other group A opponents Shakhtar Donetsk and Real Sociedad of the walk-in-the-park variety.

Stefan Kiessling - with 4 goals and 3 assists this season - is impressing everyone except Germany coach Joachim Löw. And Sidney Sam (4 goals and 2 assists) is finally living up to his great potential since Andre Schürrle's departure to Chelsea.

No one expects Leverkusen to go six for six in this group, but if they play within themselves and keep doing what they do best (i.e. find Kiessling) they should be able to survive until the knock-out stage. How far they progress after that will depend on the draw.

Schalke 04

Of the four German Champions League participants, Schalke is the one that scraped into the competition. They needed results to go their way on the final day of last season to secure fourth place and barely squeaked by Greek side PAOK in the qualifier. So it's perhaps fitting that ahead of Wednesday's home match against Steaua Bucharest, they beat Mainz by the narrowest of margins 1-0.

The goal-scorer in that game, late transfer Kevin Prince-Boateng, is a definite upgrade on Jermaine Jones, combining the American national's muscle with far greater skill on the ball. And the Royal Blues should be given a boost when striker Klaas-Jan Huntelaar finally returns from a long-term injury.

Still there's a nagging sense that Jens Keller isn't really a big-time coach. And Schalke will need to put together a string of wins before anyone becomes a believer. The Steaua match should be a litmus test.

If Schalke prevail in that one, they should reasonably expect to finish at least second in a Group E that also includes Chelsea and Basel. If they can't handle the Romanian side in front of their home crowd, it's hard to see them going far at club's football's ultimate level.