Champions League 2013: Biggest Goal-Scoring Threats to Watch For in UCL 2nd Legs

The UEFA Champions League will provide two magnificent semifinal matchups this week when both Real Madrid and Barcelona seek to keep their European dreams alive.

Beaten comprehensively by Borussia Dortmund and Bayern Munich, respectively, in the first leg, the Spanish giants will know that they need to score plenty of goals if they want to stage a sensational comeback here and move through to the final.

Similarly, both German sides will know that if they can find the back of the net in this one, then their challengers' hopes in the competition will be dashed.

So with all four teams looking for goals, it's bound to be a magnificent week of Champions League football, with plenty of highlights and talking points. 

Who are the biggest goal-scoring threats to watch for from each team this week?

Read on and find out.

Bayern Munich: Arjen Robben, LW/RW

It'll be interesting to see whether Jupp Heynckes starts Mario Mandzukic or Mario Gomez in the starting role here. Mandzukic has been the preferred striker in the Champions League, but after missing last game with suspension, he was replaced by Gomez—who did a very good job in attack.

Still, with his star player available for selection once more,  you'd have to think that Mandzukic will get the nod here, and will no doubt be a huge threat on the night. However, he won't be as big of a threat as that of Arjen Robben, who should see plenty of opportunities in this one.

With Bastian Schweinsteiger sitting on the brink of yellow-card suspension, it's hard to see him starting here—so expect Robben to keep his starting spot.

The mazy winger was superb against Barcelona's defense in the first leg and will look to carry that form through to the second leg also. He has four goals and four assists in his last seven games, and with Bayern's depth of attack around him, will be a constant issue for Barcelona on the night.

Bayern will look to defend stoutly and try and hurt Barca on the counterattack, which will suit Robben's skills and help him be most effective for the Bavarians.

Barcelona: Lionel Messi, ST

There have been several truths about Lionel Messi season—that he is brilliant, that he is a goal-scoring machine and that he was completely shut down against Bayern Munich in the first leg.

Messi was unable to get the ball and inject any real significance at the Allianz Arena and will look to rectify that when he takes the field this week. His hamstring will have had another week to heal and give his confidence more time to grow, which should see the goals flow in as a result.

The Argentinian star has chalked up 44 goals and 12 assists this season, but he has scored just two goals and an assist in his last four games. I use the word "only" there not to portray that those are poor numbers, for they're not. However, it is his statistically worst four-game period of the entire season, and with two of his lowest match ratings in that time as well, his form really isn't that great.

However, as we all know too well, Messi is capable of turning that on its head in an instant. The goal he scored against Athletic Bilbao on the weekend was simply mesmerizing, and he'll be a huge problem for the likes of Dante and Manuel Neuer to deal with throughout the night here. 

Even if Bayern do have a four-goal lead under their belt.

Borussia Dortmund: Marco Reus, CAM/LW

After his goal-scoring heroics in the first leg against Real Madrid, it might seem surprising that Robert Lewandowski isn't being touted here as the biggest threat.

After all, he is the team's leading goal-scorer in all competitions and has been simply superb this season. And he scored four goals one game against Real Madrid! I mean, how is he not being considered the biggest goal-scoring threat to watch here for Dortmund?

Perhaps the biggest point to remember is that Lewandowski was able to have such a dominant night thanks to a woeful defensive performance from Pepe. 

Jose Mourinho is not going to allow that to happen again, and I would be surprised if the more sound and stronger Raphael Varane isn't shifted on to Lewandowski—which could well influence the attacking chances afforded to the striker. 

Also, keep in mind that given the nature of this game Madrid will be attacking Dortmund, and Dortmund trying to hurt Madrid on the counterattack.

And when it comes to the counterattack, Marco Reus is the man who thrives the most for the Germans. He has scored four goals in the Champions League so far and 12 in the Bundesliga, and his brilliant running in open space makes him a huge threat for Dortmund in this one.

Lewandowski and Mario Gotze are great distributors and more than capable getting Reus on the score-sheet here, especially having already scored at the Bernabeu this season.

Real Madrid: Cristiano Ronaldo, LW

It's been a week from hell for Ronaldo with defeat, injury and affair claims all dominating the headlines—which is not what he would have wanted in the buildup to his biggest game of the entire season.

Madrid will need him to fire if they're going to come back against Dortmund, and given his dominance in the Champions League so far, that seems likely.

Ronaldo is the leading goal-scorer in the competition this year and has recorded more shots on target in the Champions League than any other player. He might have been shut down by Dortmund through the three games that they've played, but he's still managed to chalk up two goals.

The star winger has 14 goals and three assists in his last 12 games and given Madrid's need to attack, he'll be a constant threat for Dortmund here.

I can't see it being enough to bring Los Blancos back from a three-goal deficit, but Ronaldo is certainly more than capable of finding the back of the net in this one.

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