The Saints surprised everyone by taking the lead in north London thanks to Cameron Archer, but Havertz equalized just before the hour mark.
It was Saka who provided the assist for that goal – and he made it two when he set up Gabriel Martinelli in the 68th minute to turn things around.
Saka then got on the scoresheet himself with just two minutes of normal time left to wrap up a superb individual performance and maintain the Gunners’ unbeaten start to the season.
It’s now seven assists this season for Saka – more than any other player in Europe’s top five leagues – and Arteta believes it’s clear that the 23-year-old has taken another step in his career with his level of performance so far this campaign.
‘He’s taken another step ahead in what he does and especially when [he does it],’ the Spaniard said in his post-match press conference.
‘[He can] do it at home, do it away, do it in big games, in the not-so-big games and when the teams need not when it’s already 3-0. That’s what defines a top, top player.
‘What he is doing at his age is unbelievable.’
Havertz’s goal, meanwhile, makes him the first Arsenal player since Robin van Persie to score in seven consecutive home games and Arteta believes the German has also reached another level with his consistent output in front of goal.
‘You can tell [his confidence has grown],’ Arteta added. ‘The way he holds the ball, the positions he takes in the box. He’s an attacking midfielder but he plays as a nine so you don’t know where he is.
‘That’s his football brain and for sure his focus now is “I’m going to win the game, I’m going to do it” and that’s a different thing.
‘He’s practising and he wants more. He’s not satisfied with what he is doing because there is still another level for him.
‘He’s surrounded by incredible players but something has changed in him and that confidence you really sense it. And now he’s scoring in games and winning football matches which is great.’
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