The former FC Cologne man made his Premier League debut in Saturday's 0-0 home draw with Sunderland and although he found life tough in his first outing, his fellow German is backing him to get among the goals once he settles into North London life.
"It was tough for him (on Saturday) because it was his first game up front," Mertesacker told Arsenal Player.
"He will get used to the game, switch on quickly and score a lot for us.
"You have seen that he has a good technique and he is good in possession.
"We have the players who can pass the ball. He is a good finisher too and we will see that in a couple of weeks."