The Gunners maintained their place at the top of the table thanks to a 2-1 win on Monday night, with the north Londoners a point ahead of Manchester City and two in front of Chelsea.
And the 29-year-old, who made his 100th appearance for the club at Villa Park, was delighted to help Arsene Wenger’s men grind out a crucial three points.
“It was very important to respond and for the other teams to see that Arsenal is alive and that we can respond to anything,” said Mertesacker.
“We just look at ourselves and think we are good enough to respond to any challenge they give us.
“It is really tight at the top. At the moment, there is no chance to drop any points.
“We have to show the other teams that when we feel the pressure we can respond. That is vital so I’m really happy with the fighting performance in the second half and how resilient we were.”
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