"I don't know - it can happen", Wenger said, when asked if he knew why Ozil had been underperforming. "That will be the key".
The North London club last won the Premier League in 2003-04 and have failed to mount a proper title challenge since then.
Oxlade-Chamberlain however will not dwell on what has gone before even though Arsenal have not gone past the Champions League round of 16 stage in the last six seasons.
The Gunners defensive difficulties were not helped by the knee injury Mertesacker suffered during pre-season, with the former Germany global hopeful of returning to the Arsenal squad sooner rather than later.
Arsenal have been defeated in the first leg of their Champions League round of 16 tie in each of the last five seasons.
He netted 60 seconds after Arturo Vidal's 90th-minute goal to get Bayern out of jail with a 2-0 win last Saturday at relegation-threatened Ingolstadt.
Arsenal officials have offered Arsene Wenger a new two year contract but with the Arsenal supporters are not entirely convinced the Frenchman can turn things around, they are preparing for life without Arsene Wenger.
'That is why Bayern will show its true face in the Champions League.
"I haven't seen them play, I always follow the results and the media reports and keep in contact with Carlo", Clement added.
Wenger, however, denied that he was ready to quit after yesterday's 2-0 win over Hull City.
"You can't do what we did against Watford, where we gifted them two goals, or what we did against Chelsea, where we lacked that bit of intensity at times".
"They've got some real world-class players in (Mesut) Ozil and (Alexis) Sanchez particularly, he could play for any big team in the world".
William Gallas, who played under both managers and won the Premier League under one, highlighted exactly what made the Portuguese so different to his French counterpart.