Vieira had an immediate impact, getting on the ball and dictating proceedings, and he collected an assist with an excellent first-time pass to Gabriel Jesus – who raced clear, sat down Diogo Dalot and rolled the ball past Andre Onana.
The 23-year-old, who struggled in his first Premier League campaign, is yet to start for Arsenal so far this season but has now influenced back-to-back matches.
In Arsenal’s previous outing against Fulham, Vieira won a penalty which Bukayo Saka converted to draw the Gunners level and then played an excellent cross to Eddie Nketiah to take the lead.
He has three goal involvements in just 47 minutes of Premier League action whereas £65million summer signing Havertz – who has started all four matches so far this season – is yet to register a goal or assist.
While Arteta continues to defend Havertz’s performances, he was full of praise for Vieira’s impact against United and feels something has clicked with the Portuguese midfielder this season – and he is very much in the mix to play a bigger role.
Asked if Vieira might start Arsenal’s next match against Everton after the international break, Arteta replied: ‘Every player has a chance to do that.
‘Today we decided to start with Kai, we knew that Fabio would have a big impact especially in the last few minutes, or final minutes if we needed something.
‘Something has changed with Fabio, you notice with the crowd when he steps in he is different to how he was last year.
‘He’s more mature, he’s more senior in the squad and his confidence in the squad is high so I’m really happy to have those options.’
Havertz, meanwhile, is struggling to live up to his massive price tag and had another disappointing game against United, air-kicking a great opportunity to score before gifting possession to the visitors to launch the counter-attack from which Marcus Rashford netted.
Asked what is going wrong for the German, Arteta told Sky Sports: ‘I said to him yesterday, things are a little bit hard at the beginning.
‘When I met my wife at the beginning it was hard to conquer her. I had to try, and message, and go and go and when she said, “Yes I want to be together” then it’s beautiful.
‘If she said yes on the first day then it’s not that great, so it’s good. I think the crowd was really good with him today.’
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