United currently lead second-placed City by two points but can extend their advantage at the top to five with victory at Blackburn Rovers on Monday night.
And Rooney – who has been in prolific form this term, netting 29 goals for the Red Devils – admits that triumphing ahead of their local rivals would make their 20th league title that little bit sweeter.
“Would it mean something extra because City are challenging? Yes, of course,” Rooney told the Sun. “It’s the first time since I’ve been here and the first time for many years that United and City have been going head-to-head for the title.
“To win it would be great for the players, the fans and the club as a whole, and it would definitely be one of the best titles we’ve ever won, if we can do it.”
The 26-year-old believes that the English top flight has improved dramatically over the last few seasons.
“It’s probably more challenging than it has ever been in the Premier League to win the title,” he continued.
“You have to be at your best in every game. You can’t perform at 75 per cent of your capabilities and expect to win it. The league in general has got stronger over the last few years.
“You used to have the usual top four teams and then everyone else playing for the other positions. Now there is six or seven teams vying for a top-four place.”
Rooney also hailed United’s never-say-die attitude, and praised his side for securing results even when not producing the most convincing displays.
“We have played some great football at times and other times when we haven’t played so well, but we’ve shown spirit and determination to grind out results,” he said.
“If you look at our points tally for this stage of the season, it’s probably one of the highest in United’s Premier League history, so we haven’t done too badly.
‘We’re not really too concerned what people say as long as we keep winning games.
“The most important thing is for us to concentrate on ourselves and make sure we take care of our results, but of course it does give you a real boost when you see your rivals drop points.
“We just need to keep winning to ensure we take advantage of that, if and when it happens.”
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