By Karolos Grohmann
BERLIN (Reuters) - Arsenal's Jack Wilshere and Kieran Gibbs are doubtful for the Champions League Group F trip to last season's runners-up Borussia Dortmund with coach Arsene Wenger eager to make amends for last month's loss to the Germans.
Wenger spoke last week of the "important period" the Premier League leaders are going through - the trip to Dortmund in between Premier League games against Liverpool, whom they beat 2-0 on Saturday, and Manchester United.
The win over Liverpool in the top-of-the-table clash was particularly satisfying for Wenger, who told reporters: "That is as well as we have played all season.
"People have been skeptical about us so far this season but today will increase our confidence and get the fans right behind us."
Arsenal, though, have a significant challenge to meet against Dortmund, whose late 2-1 victory over the Gunners at the Emirates Stadium last month left them level on six points with the north London club and Napoli as the Champions League group stage reached its halfway mark.
Wenger is expected to be without Wilshere and could also miss Gibbs while he also needs to see progress on Mathieu Flamini, who missed the win over Liverpool.
Defender Gibbs went off holding his calf in that game while Wishire injured his ankle in training last week.
Dortmund are riding a wave of optimism after crushing VfB Stuttgart 6-1 on Friday following their derby win against rivals Schalke 04 a week earlier.
Poland striker Robert Lewandowski notched a hat-trick as Dortmund produced another scintillating display of attacking football.
Coach Juergen Klopp, who praised Wenger's style of play, could have captain Sebastian Kehl back in the squad after he recovered from injury and has returned to training.
"(Arsene Wenger) is really something. He is Sir Arsene Wenger," Klopp told reporters.
"But he likes having the ball, playing football, passing it. It is like an orchestra but it is a quiet song. I prefer heavy metal. I always want it loud," said Klopp, who last week extended his Dortmund contract by two years to 2018.
"I like Arsenal's philosophy but I cannot coach it, I am a different guy," said Klopp who will be back on the bench after sitting out the last two games with a suspension.
His teams won both matches with him in the stands following an outburst in their opening defeat to Napoli.
(Reporting by Karolos Grohmann,; Additional reporting by Steve Wood; Editing by Justin Palmer)