The Champions League gets back underway this week with the final leg of the quarterfinals. A few matches are pretty much settled while most have some interesting storylines that are worth considering.

Real Madrid vs. Borussia Dortmund

This match is pretty much in the bag for Los Blancos. With a 3-0 aggregate lead Dortmund would need to put together a 4-0 or 5-1 win in order to dream of making the semifinals. A year ago, the team managed a 4-1 win at home, but this is not the same Dortmund side as it was in last season's semifinals. And this is not the same Real Madrid either. Under Jose Mourinho, Los Blancos were disorganized and tentative. Under Carlo Ancelotti, they attack with freedom and look lethal offensively.

Will Cristiano Ronaldo play and score the record-breaking 15 goal of the UCL season? He did not play the last game for Madrid due to an injury and it is still possible that he misses out on Tuesday. If he does play he will be the man to watch.

Barcelona vs. Atletico Madrid

Los Cules have to score to have any hopes of a semifinal berth but they may find it hard to unlock their opponents. Atletico Madrid has only conceded 22 goals in the Spanish League; the team has not lost at home this season and has only allowed nine goals at the Vicente Calderon. Inversely, Barcelona has 10 wins, three draws and three losses away from the Camp Nou and has conceded 15 times. Blaugrana has not had the creative flair in recent weeks and could find itself shutout. More importantly, the two sides have battled to four draws this season; there have only been two goals scored by each side, making for a far more complicated situation for Barcelona.

Paris Saint-Germain vs. Chelsea

Most would consider a 3-1 aggregate to be a done deal, but the second leg of this tie takes place at Stamford Bridge where Chelsea has proven to be dangerous. Expect to see Jose Mourinho's troops attacking constantly in this one. The problem is that an overly aggressive Chelsea gives more space to an offensively dynamic PSG side.

The French side only needs one goal to put this matchup away for good; Chelsea needs a 2-0 win and cannot concede a single goal.

Bayern Munich vs. Manchester United

Prior to last week, few expected Manchester United to come out alive from the first game. But the team not only did that but also proved its worth in a 1-1 draw. Most expect Bayern Munich to take care of business at home, but the team is coming a loss in the Bundesliga and has not won in its last three games. Meanwhile United has looked lethal in its last few Premier League matches; expect this to be a thrilling and fast-paced match.

Which Champions League matchup do you think offers the most suspense and drama this week?