"I always felt the game was going to be in their penalty box and there's no-one better at taking these kind of chances," Ferguson told reporters.
"His positional play, his first touch and his finish were absolutely magnificent. They were world class. There's no-one better than Michael Owen."
The 29-year-old Owen divided opinion among United supporters when he joined in a surprise free transfer from Newcastle.
He scored his first Premier League goal in a 5-0 victory at Wigan Athletic but the strike against City will endear him to the fans much more.
"If there was any doubt before then maybe this has sealed the deal," Owen said. "Me coming to Manchester United was always going to create a bit of noise. But even if they (the fans) didn't take to me it is still a privilege to play for Manchester United.
"You are never going to pass up an opportunity to play for a club like this. The fact I've scored the winner in the Manchester derby hasn't sunk in yet."
City have spent more than £120m on players in a bid to challenge their local rivals and they fought back three times to equalise before Owen's strike.
"Sometimes you've got a noisy neighbour and you have to live with it," Ferguson said. "You can't do anything about them and they keep on making noise.
"But what you can do, and what we've shown today, is that you can get on with your life, put your television on, turn it up a bit louder and as the players showed their playing power and that's the best answer of all."
City manager Mark Hughes was seeking an explanation from referee Martin Atkinson as Owen's goal came five minutes and 26 seconds into four minutes of added time.
"I'm not going to question his integrity – I just want an explanation," Hughes said.
"It would be nice to get one but I don't think I'd get one. I've looked at the videos and I just can't see where he's got it from."
