Arsenal will take on North London rivals Tottenham at the Emirates Stadium in the Premier League on Sunday.
Former Germany international central defender Mertesacker is likely to start the derby for the Gunners, and ex-Arsenal forward Nicholas believes that Tottenham striker Harry Kane will fancy his chances against him.
"Mertesacker was awful (at Bayern),” the former Scotland international told Sky Sports. ”I worry about him for the weekend.”
“Harry Kane, if he's fit and ready, will fancy his chances this weekend of getting at Mertesacker,” added Nicholas.
Mertesacker is a very experienced defender, but he is slow and appears to be past his prime.
The 31-year-old was one of Arsenal’s worst players against Bayern Munich in the Champions League Group F game on Wednesday.
Tottenham striker Kane has returned to form and is scoring goals again. The England international’s movement and ability to find space for himself is certainly going to be a problem for Mertesacker.
Arsenal are second in the Premier League table at the moment, while Tottenham are five points behind them in fifth.