The Magpies took the lead in the 14th minute when Hatem Ben Arfa fired home at the near post to cap a sweeping break by the visitors.
But their advantage lasted just 55 seconds as Robin van Persie netted his 26th league goal of the season when he fired home after collecting Theo Walcott’s low pass.
The game looked destined to finish all square until the 94th minute, when Thomas Vermaelen popped up to lash in from close range and move the Gunners to within a point of third-placed Tottenham.
“At the moment I maintain that because we have gone through some difficult periods and it’s very important that we keep our feet on the ground, keep our complete focus and give absolutely everything until the end,” Wenger said after the game.
“We have done that recently because we produced a great game tonight, we produced a great game against Milan and we produced a great game against Tottenham. That has to be our real target.”
He added: “We played recently against Tottenham, Liverpool, Newcastle and Sunderland, who are all very difficult to beat – and we won all of these games.
“We know every time it was very tight and we won in the last minute in three of them. There is definitely complete commitment in every single game.
“Where we finish is down to how we keep going and if we put that same amount of effort into every single game.”
Wenger reserved special praise for man-of-the-match Walcott, who has received his fair share of criticism this term but put in an impressive performance on Monday.
“I think that he is so long in the spotlight that people forget that he is 22 years old and getting now to an age where you perform,” Wenger continued.
“It is as simple as that. He develops well because he is intelligent. Tactically, technically tonight he had a complete game.”
Meanwhile, Newcastle boss Alan Pardew felt his side were hard done by after the last-gasp defeat.
“To get beaten in the last minute is really sickening for us,” he said. “Great teams score late goals but overall we deserved a point.”
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