Arteta is going through his first poor period as Gunners boss, with Arsenal losing three of their last four Premier League matches to slip to 11th in the table.
Arsenal travel to Old Trafford to face revitalised Manchester United on Sunday and Redknapp says the clash represents an opportunity for Arteta to silence any suggestion that his team are struggling.
‘It’s been a difficult run [for Arsenal]. Sometimes when you come in to a club you can make a big impact,’ Redknapp told Sky Sports’ Pitch to Post podcast.
‘Pierre-Emerick Aubameyang hasn’t hit the heights of last season so far, he’s had a bad run.
‘They’re form against the bigger sides has been better and you’re facing a United team who didn’t look comfortable against Chelsea.
‘If they can start the game well they will see it as an opportunity to get a result.
‘Arteta was doing such a good job for a while but it doesn’t take long for it turn. You only have to lose a few games and the focus turns on you.
‘Mikel will be well aware of that.’
Redknapp also discussed Arsenal’s move for Thomas Partey and says the Ghana midfielder will be a ‘huge player’ for the Gunners.
Arsenal completed a deadline-day move for Partey after meeting his £45m Atletico Madrid buy-out clause.
‘Arsenal have got a good manager there but they need to sign some players,’ Redknapp added.
‘Thomas Partey is going to be a big signing for them. They need to get him in the team to give them some power and stability.
‘He’s going to be huge for them. You want to get that big result to quiet it [the criticism] down. It’s a big game for both sides.’