Arsenal have never won the Champions League but were losing finalists under Wenger in 2006
Dinamo Zagreb 2-1 Arsenal: We were unlucky – Arsene Wenger
Arsenal manager Arsene Wenger claimed his side were "a bit unlucky" after a 2-1 defeat by Dinamo Zagreb in their Champions League opener.
Wenger made six changes for the game after Saturday's Premier League win over Stoke.
The Gunners had Olivier Giroud sent off after 40 minutes and Wenger also blamed "exceptional circumstances".
"I believe the first goal is offside and after the sending off is very harsh," said Wenger.
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‘I don’t understand the referee’
Arsenal went behind to an Alex Oxlade-Chamberlain own goal before Giroud's dismissal for picking up two bookings.
The France striker was cautioned for dissent for a decision by Romanian referee Ovidiu Hategan going against him before a second yellow card for a foul on Ivo Pinto.
"We were not at our best, but nor was the referee," added Wenger.
"The first yellow is Giroud's fault because he protested, even if it was not a foul against him. But after he should not have responded to the referee.
"The second yellow card, he is unlucky to touch the guy – he did not see him. It was accidental completely, but it happened.
"I don't understand the referee. It has to be on purpose, a foul on purpose. Then the referee should have given many yellows."
‘It didn’t work’
Arsenal have been knocked out in the last 16 of the Champions League in the past five campaigns
Wenger dropped keeper Petr Cech, left-back Nacho Monreal, midfielder Francis Coquelin and forward Theo Walcott to the bench for the game, while midfielder Aaron Ramsey and right-back Hector Bellerin were not in the squad in Zagreb.
"When you don't win the game you have to look at yourself and think you haven't got it right," said Wenger, whose side play Chelsea this coming Saturday.
"I don't believe the players who came in had a bad game but it didn't work, it didn't work.
"I have to analyse that well. It is very difficult to give a definite answer straight after the game."
Wenger remains confident
Arsenal began the Premier League campaign with a 2-0 defeat by West Ham and have again started their Champions League challenge with a defeat following a 2-0 loss by Borussia Dortmund at the same stage of the competition at the start of last season.
However, Wenger – who did not sign one outfield player during the summer – is still confident his side can qualify from a group which is currently topped by Bayern Munich after their win over Olympiakos.
"Overall, I believe we have problems to start in every competition this season. But I am confident we can put that right in the next five [Champions League group] games."
He added: "Mathematically, we can qualify without any problem if we produce our performances that we want at home."