European soccer’s most prestigious competition kicked into gear this week. The UEFA Champions League, comprised of the greatest clubs on the continent, has reached the 16-team knockout phase after a two-month winter break.

The 2011-12 tournament has already served up an array of shocks. Manchester City and Manchester United—who currently occupy the top two spots of the English Premier League—were eliminated in the group stage, while virtually unknown Apoel Nicosia became the first ever club from Cyprus to advance to the Round of 16.

Indeed, there are plenty of intriguing storylines to go around. Arsenal and Chelsea have endured terribly disappointing domestic campaigns thus far, but are the only surviving English clubs in the competition. Real Madrid has built an impressive 10-point lead on Barcelona in La Liga, but will that translate to Champions League superiority as well?

And will there be a Cinderella this year? Several clubs will be in search of the glass slipper, including lesser-known representatives from Russia, Italy, Switzerland and—as I’ve already mentioned—Cyprus. The Cinderella story in 2010-11 belonged to Schalke. The German club finished 14th in the Bundesliga but streaked all the way to the semifinals before losing to Manchester United.

Here’s a sneak peek at the 2011-12 Champions League knockout phase, which culminates on May 19 at the majestic Allianz Arena in Munich.

CONTENDERS

FC Barcelona

This is a no-brainer. Striker Lionel Messi is simply the best player in the world, while Xavi and Andres Iniesta are two of the most creative midfielders of the era. Manager Pep Guardiola has forged a dynasty, as Barcelona has won three Champions Leagues since 2006 and two of the last three.

For the first time since 2008, however, Barcelona has shown a significant chink in the armor. Questionable defending has enabled rivals Real Madrid to claim a 10-point lead in Spain’s Liga. Regardless, expect Messi and company to advance far into the tournament.

Real Madrid

Jose Mourinho is looking to become the first ever manager to win the Champions League with three different clubs (and from three different countries, no less). He won the competition in 2004 with FC Porto and in 2010 with Inter Milan. Winger Cristiano Ronaldo, to no one’s surprise, has been red-hot this season, scoring an incredible 27 goals in 21 league appearances.

Midfield playmakers Xabi Alonso, Mesut Ozil and Angel Di Maria have been in sublime form, as well, combining for 28 assists in league play. Madrid is on the verge of running away with La Liga, which could allow them to focus more intently on the Champions League in March and April.

Bayern Munich

Two months into the Bundesliga season, Bayern Munich had scored 30 goals and conceded 3. Bayern slumped in December and January and are currently second in the league, but it doesn’t change the fact that they have a world-class squad. Furthermore, the Champions League Final takes place at Bayern’s home stadium.

This team is full of German national teamers, including goalkeeper Manuel Neuer, defenders Holger Badstuber and Philipp Lahm, midfielders Thomas Muller and Bastian Schweinsteiger, and forward Mario Gomez. Throw in lethal wingers Franck Ribery and Arjen Robben, and you’ve got a legitimate Champions League contender.

AC Milan

Currently second in Italy’s Serie A, AC Milan has the attacking quality to win the club’s eighth Champions League title. When Brazilian forward Robinho and lanky Swedish striker Zlatan Ibrahimovic are in form, there isn’t a much better partnership to watch. Milan landed a tricky draw in the Round of 16 against Arsenal, but veteran experience gives them an edge: Clarence Seedorf, Alessandro Nesta and Massimo Ambrosini have already won two Champions Leagues with the club.

PRETENDERS

Arsenal

As an Arsenal fan, it pains me to include the Gunners on this list. But these are the facts: Arsenal has already lost eight Premier League matches, no one besides Robin van Persie is a legitimate scoring threat, and the club’s best midfielder—21-year-old English national teamer Jack Wilshere—has been out all season due to injury.

Manager Arsene Wenger’s has become increasingly hot, and it is unlikely that will cool any time soon. To make matters worse, the Gunners drew Italian giants AC Milan in the Round of 16—fitting for a team that has yet to really catch a break this season.

Chelsea

At the tender age of 34, manager Andres Villas-Boas has found life awfully hard in charge of Chelsea. If the Premier League ended today, the fifth-place Blues would fail to qualify for next season’s Champions League.

Luckless striker Fernando Torres remains in horrific form—zero goals in 18 matches—while defender John Terry was accused of racial abuse against an opponent on Oct. 23 and subsequently stripped of the England national team captaincy. Frank Lampard and Ashley Cole, usually the two Mr. Reliables for the Blues, are fighting constant injuries. Usually a Champions League favorite, Chelsea is in shambles right now.

Inter Milan

Things have changed dramatically for the Italian powerhouse since it lifted the Champions League trophy in 2010. Following Jose Mourinho’s departure from the club, Inter has gone through three managers and is currently fifth in Italy’s Serie A. Goal scoring hasn’t come easy for the Nerazzurri: only Diego Milito and Giampaolo Pazzini have more than three goals on the year.

Negative speculation has surrounded Inter since August, and there are rumors that manager Claudio Ranieri could be replaced in the coming months. Much like Chelsea, Inter is usually a safe pick to advance to at least the semifinals. Not the case this time around.

SLEEPERS

Napoli

This scrappy club from Naples has three of the best young talents in the game: Uruguayan striker Edinson Cavani, Argentinian forward Ezequiel Lavezzi and Slovakian midfielder Marek Hamsek.

Zenit St. Petersburg

How does playing soccer sound while it’s 20 degrees and snowing? That’s what Zenit St. Petersburg’s opponents face at this stage in the competition. Alexander Kerzhakov is one of the better forwards no one knows about while Portuguese players Bruno Alves and Miguel Danny boast significant World Cup experience.

ROUND OF 16 PREDICTIONS

The knockout phase began Tuesday and involves the sixteen teams who finished in the top two of their four-team group last fall. Each tie in the knockout phase, apart from the final, is played over two matches, with each team playing one match at home. The team that has the higher aggregate score over the two legs progresses to the next round. If aggregate scores finish level, the away goals rule is applied—that is, the team that scored more goals away from home over the two legs progresses. If the teams remain tied, they play 30 minutes of extra time in the second leg. If there is still no winner, a penalty kick shootout breaks the deadlock.

Bayer Leverkusen (GER) vs. Barcelona (ESP)

Leverkusen has been underwhelming in the Bundesliga and will surely be overwhelmed by Barcelona in this contest. The defending champions will advance easily.

Lyon (FRA) vs. Apoel Nicosia (CYP)

Apoel Nicosia has been the best story of the tournament thus far, becoming the first Cypriot club to advance to the Round of 16. The fun stops here, however. Lyon moves to the quarterfinals.

Zenit St. Petersburg (RUS) vs. Benfica (POR)

Alas, balmy Portugal versus frigid Russia. Benfica has been outstanding this season, remaining undefeated in domestic play. This one’s awfully tough to call, but I give Zenit the slight edge.

AC Milan (ITA) vs. Arsenal (ENG)

Behold the best matchup in the Round of 16. AC Milan boasts seven Champions League titles, while Arsenal is still seeking its first. Milan compounds Arsenal’s misery by advancing.

CSKA Moscow (RUS) vs. Real Madrid (ESP)

CSKA is no slouch, but they are running up against probably the hottest team in Europe right now. Madrid simply has too much firepower to be beaten at this stage.

Napoli (ITA) vs. Chelsea (ENG)

The second-best matchup of the round features Napoli’s youths versus Chelsea’s veterans. Chelsea owner Roman Abramovich has invested millions to forge a Champions League winner, but he’ll have to wait another year. Napoli will advance narrowly.

FC Basel (SUI) vs. Bayern Munich (GER)

Basel shocked the world by knocking out Manchester United in its final group stage game. But they don’t have enough magic to thwart the Germain powerhouse.

Marseille (FRA) vs. Inter Milan (ITA)

This is an underrated matchup, and the team that wants it more will probably advance. Inter is pretty desperate at this point, so I expect them to squeak through to the quarterfinals.