The German giants are the current holders of the European trophy – which they won alongside their domestic league and cup competitions last term – and have been in fine form once again this season.
They are currently 16 points clear at the top of the Bundesliga, and have been playing some excellent football under new manager Pep Guardiola.
Arsenal meanwhile have been in a mini slump of late, with some below par performances having seen them slip from the summit of the Premier League.
They were knocked out of the competition at the same stage by Bayern last year, and Mertescaker admits that he is wary of their opponents once again, but that he’s hopeful they can draw on past experiences over both legs:
“Bayern are untouchable at the moment, both in the Bundesliga and in Europe,” he is quoted by the London Evening Standard.
“The only thing that makes me positive is that we beat them in Munich last year.
“That allows us to go into the game with a certain degree of faith. We’re going to give it our best.
“They’re a little bit better in every department under Pep Guardiola, they’ve set a new benchmark.
“We’re going to have to get a different result this time because the 3-1 defeat practically decided the tie last year. That was the decisive game.”