Champions League 2013-14: Showcasing Most Captivating Fixtures This Week

Although the Champions League doesn't start getting really good until the knockout stages, there are still plenty of entertaining fixtures that will kick off the competition this week.

Some of the complaints about the group stage are valid. It is a bit watered down with teams that have almost no chance of making it through, and the bigger clubs will lock up a spot in the round of 16 with a few matches left in their club.

However, this early in the tournament, nothing is assured. There are plenty of deep groups that have three or even four clubs that could realistically earn first- or second-place position.

Here's the full slate for this week's Champions League action, with the four most interesting matches highlighted and broken down more in depth.

Manchester United vs. Bayer Leverkusen

David Moyes really needs a win in his first Champions League fixture. He's not had the best of times since becoming Manchester United manager, and a win over Bayer Leverkusen would be a great start to the club's European campaign. Whatever he can do to get the supporters off his back is a good thing.

United are coming off a 2-0 win against Crystal Palace in what was their best performance of this young season. Adnan Januzaj and Marouane Fellaini came off the bench and put in good performances, giving their side a different dimension in the process.

Beating Palace convincingly isn't the best barometer for success. United will need to be much better than it has been in its toughest tests of the season—home against Chelsea and away to Liverpool.

Bayer Leverkusen are third in the Bundesliga table and haven't missed a step despite losing Andre Schuerrle and Daniel Carvajal this summer. Stefan Kiessling and Sidney Sam each have four goals and have combined to get five assists.

This should be a very interesting matchup.

Marseille vs. Arsenal

Arsenal's European campaign got a whole lot more interesting after Mesut Ozil made the move to the Emirates. He alone isn't enough to make the Gunners title contenders, but he should allow them to advance a little deeper into the knockout stages.

Arsenal are playing a lot better since that opening week loss to Aston Villa. They're much more fluid in the attack, and Bacary Sagna has become a very stable centre-back.

Marseille are looking to snatch that third place in the Ligue 1 table. The spending of Paris Saint-Germain and AS Monaco has made it harder for other French clubs to get a shot at the title, but Marseille are giving it their best shot. They're fourth in the table and have gotten a lot from summer signing Dimitri Payet.

Group F is arguably the toughest Champions League group from top to bottom, so it will be important to start the campaign off on the right foot.

Napoli vs. Borussia Dortmund

This will be the battle of the table-toppers as Napoli have taken the full nine points from their first three matches to get a two-point lead on the clubs in second place in Serie A, while Borussia Dortmund are also perfect in their league, going 5-for-5 to get a two-point lead on Bayern Munich.

In terms of matchups, it doesn't get much more hipster than this. Both clubs have been very successful in the past, but they've attracted a lot of admiration lately for their style and success.

Dortmund won't be surprising anybody this season after making last year's final. Even with the loss of Mario Goetze, Juergen Klopp has his side really looking good. Pierre-Emerick Aubameyang has hit the ground running in Germany, including getting a hat-trick in his first Bundesliga start.

On the other side, Napoli have improved in the summer, from the hiring of Rafa Benitez to the signings of Jose Callejon, Raul Albiol and Gonzalo Higuain. They also brought in Pepe Reina on loan. Under Benitez, Napoli should be much more competitive in Europe. He's got a good pedigree in Continental competitions and won't be hindered tactically like Walter Mazzarri was.

Barcelona vs. Ajax

This one won't be all that even on the pitch. Barcelona are one of the best clubs in the world, and Ajax haven't made it past the group stage of the Champions League since 2005-06. FOX Soccer's Leander Schaerlaeckens also pointed how how the reigning Dutch champions are facing off with PEC Zwolle before their UCL match.

Barca should be able to dominate this fixture, especially playing at home. The Amsterdam side will be lucky to snatch a goal, and anything less than a loss would be a great result.

What's cool about this fixture is how much they have combined to bring to world football through the decades.

It was former Ajax manager Rinus Michels who helped bring Johan Cruyff from Holland to Barcelona. They combined to win one La Liga title in 1974 and usher in the era of "Total Football" at the Camp Nou.

Cruyff would eventually become manager, with his "Dream Team" winning the 1992 European Cup in the midst of a run of four straight La Liga titles.

One of his key players was Pep Guardiola, who would go on to bring three league and two European titles to Barcelona as manager.

Ajax and Barcelona have one of the more unique relationships in world football. Even in the event this match turns into a one-sided blowout, it will be fun to watch the two clubs meet on the biggest stage.