Borussia Dortmund vs. Arsenal: Key Issues to Shape the Champions League Clash

This week welcomes the return of the European Champions League as Bundesliga side Borussia Dortmund welcome Premier League giants Arsenal to their famous Westfalenstadion for the first big clash of Group D. 

Jurgen Klopp and Arsene Wenger will both fancy their chances in this tight affair, as these two European goliaths of the continental game smash horns once again in the preliminary round of the tournament. 

With so much at stake, the factors that could win or lose the game for either side are limitless, yet fortunately, we have gone to the trouble of noting the most important of them all for your benefit. 

Here are the key issues that will likely affect Dortmund vs. Arsenal on Tuesday night. 

1. Dortmund's Defensive Frailties

Martin Meissner/Associated Press

One of the most troubling aspects of Dortmund's recent performances that will undoubtedly plague the minds of the home support on Tuesday night is their inability to keep a clean sheet against each and every opponent this season. 

Oddly enough, it has been Bayern Munich of all sides that have proven to be the only club that haven't managed to score against Klopp's team in cup and league competition. That suggests that this travelling London side may well enjoy some success in front of Roman Weidenfeller's goal. 

If Dortmund are to take all three points on Tuesday, they'll have to make sure their defence is up to the task of overcoming this mighty foe. 

2. Mesut Ozil's Form

Kirsty Wigglesworth/Associated Press

In quite an ironic twist, it is Arsenal's own German star that looks to face the most pressure on Tuesday as critics and fans alike question just what Mesut Ozil can provide against this Bundesliga opponent. 

With new stars arriving at the Emirates Stadium this summer, the recent World Cup winner doesn't enjoy the luxury of time or patience among an Arsenal support that has grown hungry for success with additional funds to Wenger's transfer budget. 

The north London club are now a side full to the brim with excellent talent and certainly have no time for a player who has no intention of getting over his slump in form. 

3. Arsenal's Defensive Frailties

Kirsty Wigglesworth/Associated Press

In what should prove an enticing affair for any neutral fans, Arsenal seem to share a reluctance to defend that may well match Dortmund's own inadequacies at the back.

In six competitive fixtures this season, Wenger's team have done little to convince critics of their defensive solidity, conceding six goals along the way. 

Interestingly enough, it was only Besiktas, a lowly opponent in the Champions League qualifiers, that have failed to score against Arsenal, with stronger opponents such as Manchester City and Everton both bagging two each in the league. 

4. No Marco Reus

Frank Augstein/Associated Press

Although Dortmund's defensive record will trouble most fans, it'll be the injury to one particular star forward that will quell any overly optimistic hopes on Tuesday night. 

Marco Reus, the figure of so much attention over the summer transfer window, will be injured for this opening Champions League tie, forcing Klopp to find other alternatives in his attacking line-up. 

The return of Shinji Kagawa will certainly help—especially after the Japanese international scored on his return to the club on Saturday—but nobody within this team can replace a player like Reus.

He'll be a miss for Dortmund and will almost undoubtedly lower their chances of a confident victory on the night. 

5. Dortmund's Shaky Home Form

Andres Kudacki/Associated Press

On the face of it, Dortmund's home record within the Champions League over the past few seasons looks pretty solid. 

Over the course of the last 11 games at the famous Westfalenstadion in Dortmund, the local side have lost just two games while winning the other nine quite comprehensively. 

Yet those two defeats came last season, taking their record down from six undefeated matches at home in the 2012/13 season to three wins and two losses the following year. 

With Arsenal's notable record on the road in such a competition, Klopp will be wary of just what has happened to his side's famous record on the night. Tuesday may well prove to be the perfect opportunity to start rebuilding that impressive home tally. 

7. Past Meetings

Frank Augstein/Associated Press

In what can only be described as a remarkable coincidence, Dortmund and Arsenal will face off against each over two legs for the fourth time in the Champions League's recent history. 

Both clubs were chosen to face off in the group stages of the European competition in the 2002/03, 2011/12 and of course the 2012/13 seasons, with this year making it four and the third in a row. 

Over the course of those three campaigns, Arsenal have taken the edge with three wins to Dortmund's two while both sides opted to share the points on just one occasion. 

It was last season's duel that proved most interesting, as both clubs overcame a home advantage to claim victories in the other's own stadium—Arsenal winning 1-0 in Dortmund while the German side beat the Gunners 2-1 in London. 

These are two sides and two managers who know each other back-to-front and should be raring to go for yet another showdown.