The Champions League returns on Tuesday afternoon with the first two Round of 16 matches.

The competition is arguably one of the most hotly anticipated of the annual soccer season, and this is the phase where things get most interesting.

But it has been a long time since we have seen teams play. In fact, the group round ended in December, and teams have undoubtedly altered their styles and are in different form.

So which teams are now the favorites to lift the European trophy based on current form?

16. FC Basel

The Swiss side struggled to get through to the knockout rounds and has only played three games since the UCL first round ended. There have been no losses, but this is not a team with a lot of fire power and one that will take on a solid Porto side that has won 10 of 13 since winning its group in the Champions League.

15. Shakhtar Donetsk

In a different year, this team is a strong candidate to make a run into the next round. But not when it is taking on almighty Bayern Munich. The German side might be going through questionable form, but there is no doubt that Munich will win this tie.

14. Bayer Leverkusen

The German side botched an easy group in the qualifying rounds and now has to take on a solid Atletico Madrid side that is still a top contender to win it all. The team has just two wins in its last seven games, which does not bode well for its success in this tournament.

13. Schalke 04

The German side has won three of its last seven and drawn two, but it must take on the defending champion Real Madrid in a rather lopsided tie. Last season, Los Blancos pummeled Schalke 9-3 over two legs, but it will not be that easy for Real Madrid this season. The German side is much improved and could shock a Spanish side that has seen better days.

12. Monaco

The French side has to take on an Arsenal side that is currently firing on all cylinders. Few had Monaco making a deep run in this tournament, but the French side has surprised and could still take down a Gunners team that has a penchant for imploding in this competition over the last few years.

11. Borussia Dortmund

Maybe this is a bit generous for a team that is battling to stay in Germany's top division. Dortmund is on a two-game winning streak, but that came on the heels of a six-game winless streak dating back to December. Jurgen Klopp seems to know how to get this team in high gear in this competition, so it should not surprise anyone if Dortmund suddenly plays like a different team against Juventus in its Round of 16 match-up.

10. Porto

The Portuguese team has been in fine form over the last month with just one loss in its last 12 games (and 10 wins in that stretch!). The team has an easy first round date with Basel and could make a surprising run into the semifinals with a favorable draw in the next round.

9. Arsenal

The Gunners get an "easy" tie in this game (you get to say that when you do not have to play Bayern Munich for the third straight year in this round). That said, the team needs to continue its recent string of solid play against a tricky Monaco side. Moreover, Arsenal still has a long way to go to make a truly deep run in this tournament.

8. Manchester City

Now we start seeing the teams that on paper should be making deep runs depending on their first round results. Manchester City's ranking has a lot to do with taking on a Barcelona side that at the moment looks unstoppable. Manchester is no slouch, but it has just one win in its last six matches. Earlier this year it looked like this team could take down Barcelona, but it has seemingly picked the worst time to slump.

7. Paris Saint-Germain

Zlatan Ibrahimovic has not been in the best form of his career this season, and it might be an indication that father time has come to collect. But this is still a solid side that could go on a run if it overcomes the hurdle that is Chelsea. That will be a tough assignment, but it is not an impossible one. And if Ibrahimovic catches fire, watch out!

6. Juventus

This is one of those now or never years for the Italian champs. Andrea Pirlo and Gianluigi Buffon are past their primes, and the team will soon need to find replacements. That said, Carlos Tevez and Paul Pogba are having tremendous years and should help this team continue its strong play. Dortmund is not a hurdle too difficult to overcome, and Juventus is capable of upsetting one of the other big horses left.

5. Atletico Madrid

Yes, this team torched its crosstown rivals, but Atletico has actually shown some difficulty in taking out other teams that it should beat. This team has the never-say-die attitude coupled with some skill (looking at you Antoine Griezmann and Koke). But does it have the fortitude of mind to make yet another deep run? Good draws (particularly Real Madrid) could go a long way toward determining this side's future in this tournament.

4. Real Madrid

On current form, the defending champions might not even make the Top Five. But this is still a team with tremendous talent that went on a 22-game winning streak earlier this year. There are certainly concerns as far as defense and goaltending goes. The offense could use a boost from its venerated BBC (especially Cristiano Ronaldo who is slumping horribly), but the midfield should improve once Luka Modric and James Rodriguez are back in the fold. The team should beat down Schalke (maybe not 9-3), but avoiding Atletico for the rest of this tournament is tantamount.

3. Chelsea

The Blues are the cream of England and have looked unbeatable at times all season long. Cesc Fabregas has been the glue keeping that midfield in motion, while goalie Thibaut Courtois has been terrific in adjusting to the Premier League. This a team that looks like it can counter like the best of them and hold possession like the best sides in the world (the top two on this ranking). Beating PSG would do a ton to boost the squads confidence overall.

2. Bayern Munich

The German side was not in optimal form heading into its matchup against Hamburg. It had lost 4-1 at Wolfburg and drawn at home against Schalke. A 2-0 win over Stuttgart did little to assuage fear. But the 8-0 win over Hamburg was nothing if not a relentless exertion of power and authority. This team is finally rounding back into top form and that alone could spell death for any team.

Any team except maybe . . .

1. Barcelona

Remember that crisis everyone was talking about in December? The top three could not find chemistry. The team's defense was a disaster.

Now, Barcelona has won 11 straight, including six wins by three or more goals. Lionel Messi is in the dynamic goalscoring form that he showcased in 2012 when he scored 91 goals in the entire year. Neymar and Luis Suarez are gelling with Barcelona's main talisman, and the defense is finally looking as solid as it did at the start of the year. Not to mention the fact that this team has dispatched Atletico Madrid three times as if it were an easy task. No one should want to take on Barcelona in current form. That is why they are favorites to win it all at this very moment.