The first leg of the UEFA Champions League quarter-finals threw up some interesting results, with FC Porto laying the groundwork for a massive upset by beating Bayern Munich 3-1 at the Estadio do Dragao, whilst Atletico Madrid were able to hold cross-town rivals Real Madrid to a goalless draw at the Vicente Calderon. In Turin, Juventus registered an unconvincing 1-0 victory over AS Monaco courtesy an Arturo Vidal penalty, giving the Serie A leaders a significant advantage going into the second leg this week. Whilst these three ties are still very much alive, Barcelona took full advantage of an injury-ravaged Paris Saint-Germain and some atrocious defending to all but seal their place in the semi-finals with a 3-1 away win at the Parc des Princes.

Bayern Munich looking to make a historic comeback against Porto

Underdogs FC Porto and Atletico Madrid Look to Cause Major Upsets As Champions League Heats Up

Pep Guardiola will be looking to overcome the 3-1 deficit and silence his critics when his team take on Julen Lopetegui’s Porto side on Tuesday night

Bayern Munich have had a tumultuous week following the shock defeat at the hands of Porto, with their famous club doctor Hans-Wilhelm Muller-Wohlfahrt leaving the club along with three other medical team members after allegedly being blamed for the loss at the Estadio do Dragao. Pep Guardiola has since claimed responsibility for the defeat, and is now faced with overcoming a two-goal deficit when his side takes on Julen Lopeteguia s Porto on Tuesday night. Bayern Munich have never gone through in a knock-out tie after losing the first leg away from home by two or more goals, although the dismantling of Shakhtar Donetsk and Roma earlier this season should give the German side plenty of hope going into the second leg at the Allianz Arena.

Porto were ruthless in their exploitation of Bayerna s defensive blunders, with the first two goals coming from Xabi Alonso and Dante being closed down and losing the ball with no defensive cover behind them. What was perhaps more worrisome for Bayern however, was their lack of penetration and inability to create clear cut opportunities. The likes of Mario Goetze will have to step up in Arjen Robbena s absence in the second leg if Bayern are to have any chance of making a comeback. Although Guardiolaa s time at Bayern thus far has undoubtedly been successful, there is a sense that the Champions League is his true test a the metric he will be judged by come the end of his reign at the Allianz Arena. Going out to Porto will only lead to more debate about whether or not Guardiola has improved the side since taking over. Particularly after the humiliating 5-0 semi-final aggregate defeat at the hands of Real Madrid last season, Guardiola needs a result on Tuesday night to silence his critics.

Ancelotti must overcome Atleti voodoo to advance to semi-final

Although Carlo Ancelotti will point to his Champions League final win over Atletico Madrid last season, his side have failed to beat their city rivals on six previous occasions this season; one of those included a humiliating 4-0 defeat at the Vicente Calderon in La Liga. The upcoming second leg is potentially a make-or-break one for the Real Madrid manager. Quite simply, failure to win the tie could result in him facing the sack at the end of the season a particularly if he isna t able to overturn Barcelonaa s slender lead at the top of La Liga.

Gareth Bale, Luka Modric and Karim Benzema are all likely to miss the clash at the Santiago Bernabeu, making the task that much harder for the reigning European champions. Diego Simeonea s side were able to stifle Real Madrid in the first leg with the aggression and defensive discipline that have typified the Argentinaa s reign at the club. Their compact 4-4-2, with all 10 men usually behind the ball, constantly forced Real Madrid out wide a negating Ronaldoa s impact to a large extent. With the score at 0-0, the importance of the first goal in the second leg cannot be overstated. If Atleti get it, their chances of going through increase exponentially; it will allow them to sit back even further and break on Ancelottia s side that will leave gaps in defence as they go looking for goals. If Real Madrid get it, however, it will draw Atletico out a a position Simeonea s men are not entirely comfortable being in. The pace and counter-attacking ability of the European champions will create all sorts of problems for Atleti once spaces start to open up in their defensive third of the pitch. Even if Ancelotti does not go on to win the competition, a quarter-final exit at the hands of Atletico Madrid would make his position at the helm of the club extremely tenuous.

Juventus must be wary of Monacoa s counter-attacking ability

Monaco would have taken plenty of positives from their narrow first-leg defeat at the hands of Juventus in Turin. The French side created several goal-scoring opportunities a a combination of poor finishing and Gianluigi Buffon keeping them at bay. Leonadro Jardima s side are at their most destructive when counter-attacking a it is how they won their tie against Arsenal, effectively ending it in the first leg by scoring three away goals at the Emirates, and it is how they troubled Juventus in Turin. The pace in their side, with the likes of Kondogbia, Ferreira-Carrasco and Martial can cause problems for any team, and it is something Juventus need to be careful about going into the second-leg this week.

Massimiliano Allegria s side are missing that extra bit of attacking verve with the absence of Paul Pogba, but the form of Carlos Tevez should provide plenty of encouragement. The Argentinian forward was at the centre of everything good for Juventus in the first leg, and as with the away second leg in Dortmund, could prove decisive against Monaco come Wednesday night. The clean sheet at home puts the Italian side in a commanding position, and with every goal they score in the second leg, Monaco effectively have to score two. Although the tie is still very much alive, it will take a special performance from Jardima s men if Monaco are to go through to the semi-finals.

Barcelona can lay down an early marker for the Champions League crown

Things went from bad to worse for PSG alarming quickly in the first leg, with Thiago Silva having to be substituted because of an injury, on top of the key players the Ligue 1 side already had sitting out the game. A less-than-fit David Luiz came on in his stead, and famously was nutmugged twice by Luis Suarez in the build-up to the Uruguayana s two goals. Unlike the other three quarter-final ties, this one appears to be over already, with the second leg being nothing more than a formality. Barcelonaa s current form a particularly that of its attacking triumvirate of Neymar, Suarez and Messi a means that the Liga leaders are extremely unlikely to be outscored by three goals come Tuesday night.

Underdogs FC Porto and Atletico Madrid Look to Cause Major Upsets As Champions League Heats Up

Luis Suarez got a brace in the first leg, and will be looking to add to his tally when Barcelona take on PSG on Tuesday night.

The game at Camp Nou, then, provides an opportunity for Barcelona to lay down a real marker for the Champions League crown. The uncertain form of the two bookiesa favourites a Real Madrid and Bayern Munich a combined with Barcelonaa s ascendency means that popular opinion is fast shifting in the direction of the Catalans, and an emphatic victory at home could only serve to strengthen their position. More than most other sides, the sheer number of game-changing individuals in Luis Enriquea s team means that even when the team isna t performing to the best of its ability, the individuals can provide moments of magic that can prove to be decisive. Indeed, that is exactly what Luis Suarez did with his two brilliant individual efforts at the Parc des Princes.

With Porto and Atletico Madrid looking to cause major upsets, and Barcelona and Juventus hoping to see out their first-leg leads, the Champions League quarter-finals are all set for a grand-stand conclusion.