Borussia Dortmund are leading Napoli thanks to a Marco Reus penalty in tonight's Group F match.
After a nervy start, Dortmund were awarded a penalty when Federico Fernandez was booked for pulling back Robert Lewandowski. Marco Reus stepped up and sent Pepe Reina the wrong way.
The home side almost extended their lead, but Lewandowski put his shot wide after Henrik Mkhitaryan had played him in with a defence-splitting pass.
Reina was then called into action again, tipping away Reus's effort as Jurgen Klopp's team searched for a second before half time.
However, Napoli showed their attacking ability when Jose Maria Callejon beat Sven Bender and crashed a low shot off the far post.
Christian Maggio then failed to cut out a Mkhitaryan pass, which found its way to Lewandowski. However, the Pole's effort was comfortably saved by Reina.
