The Gunners booked their place in the Champions League last 16 after Yaya Sanogo and Alexis Sanchez fired the north London side to a 2-0 victory over Dortmund at The Emirates on Wednesday.
We have to come back in the Premier League and that is the next target
And Arsenal centre-half Mertesacker wants Arsene Wenger’s men to show similar character against the Baggies and get their Premier League campaign back on track.
“We were very convincing [against Dortmund],” Mertesacker said. “We have to show character and that is what makes me really happy for the next few games, because we have to sharpen up in the Premier League as well.
“Saturday is a good chance to show everyone that we are still alive. We have secured Champions League [last-16] football and that gives us a life, but that has nothing to do with the Premier League.
“Dortmund are a good example of that, because they are already through but they have suffered a lot in the [German] league. We have to come back in the Premier League and that is the next target.”
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