By Karolos Grohmann
BERLIN, Nov 25 (Reuters) - Borussia Dortmund's European season hangs in the balance as last season's Champions League runners-up prepare to host Italy's Napoli on Tuesday with victory being the only option for the Germans.
Injury-hit and disappointed following Saturday's 3-0 Bundesliga defeat to rivals Bayern Munich, coach Juergen Klopp's team need to win their last two Champions League Group F games against Napoli and Olympique Marseille to preserve their chances of reaching the knockout stage.
Any other result could mean a surprise and premature exit for team that dazzled Europe last season with their lightning-quick pace and youthful exuberance but has failed to match results this campaign.
"We are lacking in determination, a sense of purpose," said Dortmund keeper Roman Weidenfeller. "We take too long to finish off a move. We pass it across instead of going straight for goal."
"Nothing has been decided yet, neither in the league nor in Europe. But Tuesday's game is more crucial than against Bayern. We have to win at home and we need to use our chances because games are won by scoring goals."
Dortmund are in third place in the group on six points, three behind leaders Arsenal and Napoli. Marseille have yet to score a point. Napoli have already beaten the Germans 2-1 in the first leg in Italy back in September.
"I told my team after the Bayern game that they have five minutes to be depressed and then just get up and keep going," said Klopp, whose team dropped seven points behind leaders Bayern.
"We have to think of the next game, draw the right conclusions and be more clear in our game. We want to have a final in Marseille (in our last group game)."
Klopp will need to reshuffle his makeshift backline yet again, with Manuel Friedrich, signed as a free agent last week after injuries to Mats Hummels, Neven Subotic and Marcel Schmelzer, being ineligible for Europe.
There is some good news, however, with right back Lukasz Piszczek returning to action on Saturday after hip surgery in the summer.
Napoli's spirits are equally low after losing their last two Serie A games without scoring, 3-0 at Juventus two weeks ago and 1-0 at home to midtable Parma on Saturday, following an excellent start to the season.
Coach Rafael Benitez rotated his team against Parma, a policy which has already been questioned by the media, and saw his side lose to a late Antonio Cassano goal in a game which could have gone either way.
Worryingly, striker Marek Hamsik, who came on in the second half, limped off after only 10 minutes, and will miss the Dortmund game with a foot injury.
Benitez blamed the international break. "We made too many mistakes but it is difficult to work well in such a short space of time," he said.
"I don't believe that my team lacks enthusiasm, though. The problem is we couldn't work the way we wanted to, the players got together on Friday after their international matches, it's not easy."
"We lost the ball too easily, allowed too much space on the counter and wasted a few opportunities going forward with Gonzalo Higuain and Goran Pandev.
"I wasn't surprised by Borussia's defeat to Bayern. I was more concerned with our result than Borussia's. We are already concentrating on the next match." (Additional reporting by Brian Homewood; Editing by Alison Wildey)