Egypt international Elneny spent last season on loan at Besitkas and it was unclear whether he would be part of Mikel Arteta’s plans for the current campaign.
However, the 28-year-old has already played nine matches for Arsenal this term and impressed alongside new signing Thomas Partey in the 1-0 victory over Manchester United on Sunday.
‘It was in midfield where Arsenal took control of the game, and that was mainly down to Thomas Partey and Mohamed Elneny,’ Keown told BBC Sport.
‘The Gunners have struggled in that area in the past, but Partey is looking like a very good signing and Elneny has made such an improvement that it feels like he is a new addition too.
‘Elneny appeared to be on his way out of the club before Arteta took charge at the end of last year. I like the way Arteta has given him another opportunity – and also how the Egyptian has taken it.
‘It is still early days, but Partey and Elneny worked really well together here and it could be the start of a really productive partnership, at least in the short term.
‘There was talk that Arteta wanted Lyon midfielder Houssem Aouar in the last transfer window as well as Partey.
‘Aouar might provide a bit more creativity in there too in the future but, for now, being solid is a good place to start.’
Keown also hailed Arsenal’s defensive improvements under Arteta, who replaced Unai Emery as Arsenal’s manager in December 2019.
‘That’s down to Arteta’s influence. Yes, they lost at Anfield and at Etihad Stadium but their defence clearly has more protection now, and there has been a change of culture to go with it.
‘There is a desire from every Arsenal player to work and scrap and get behind the ball, all over the pitch.
‘That is how you get wins at these places, and we saw that approach work on Sunday.’
Arsenal boss Arteta, meanwhile, praised his team’s efforts after they secured their first Premier League win at Old Trafford since 2006.
He said: ‘I wanted to generate belief and I asked them to be who we are as a team right now. I’m delighted because we played with a lot of courage and big personality.