The Gunners fell to a 1-0 defeat to Pep Guardiola’s side at the Emirates Stadium on Sunday with Raheem Sterling’s early goal enough to secure victory for the Premier League leaders.
Aubameyang, meanwhile, struggled to make an impact up against John Stones and Ruben Dias, although Arsenal posed little attacking threat against City throughout the game.
The 31-year-old has scored 10 goals in 22 appearances for Arsenal this season and was rewarded in September with a new contract which is worth around £55 million.
But Redknapp believes Aubameyang’s powers are in decline and feels Arsenal’s younger players are showing up the more experienced members of Mikel Arteta’s squad.
‘I look at Aubameyang… Aubameyang’s past his best,’ Redknapp told Sky Sports.
‘He’s going to have moments, he’s going to get hat-tricks.
‘When I watch him sometimes it’s like he’s lost his superpower.
‘I saw him run past people when he first came to the Premier League, I saw him run past people when he was at Dortmund.
‘I’m seeing now a player who looks like he’ll get bullied on every occasion.
‘And he’s your leading light. The likes of Saka and Smith Rowe, they’re the ones leading the way, it’s the other players who I feel have got to step up more.’
Follow Metro Sport across our social channels, on Facebook, Twitter and Instagram.
For more stories like this, check our sport page.