Alex Ferguson has rejected Roberto Mancini's claims that teams under-perform and "play with fear" when facing Manchester United.
United lead the English Premier League table by 12 points and appear set to capture the title with considerable ease, prompting City manager Mancini to suggest Ferguson's men have had plenty of help from their opponents in 2012/13.
But the veteran Scot rejected those claims out of hand, and accused his Italian counterpart of seeking sympathy as City watch the championship slip out of their grasp.
"I think that's absolute nonsense, I really do," Ferguson said.
"Because there's a lot of games I've watched, teams with City this season and I'm saying to myself, 'are they (the opposition) trying?'.
"Of course they're trying. The English game is the most honest in the world, I think we've all recognised that for many, many years. And also you've got three thousand fans following you.
"There's no way any team can come to Old Trafford and not do their best. As applies itself to the Etihad, or to Stamford Bridge, or to the Emirates Stadium or Anfield. They all do their best.
"Because that's the nature of the English game. It's absolute nonsense. Maybe he (Roberto Mancini) is looking for a bit of self-sympathy or something like that."
City, already looking beyond a disappointing domestic season, are due to play two glamour friendlies with Chelsea in the USA soon after the end of the campaign.
But with a programme of international fixtures scheduled for June, the trip is something that baffles Ferguson.
"That can only be whatever financial gains they're getting out of it, obviously," he said.
"And the two richest clubs, too. (They) need your money. I wouldn't do it, I must admit. I think players should get their rest at the end of the season. Plus the fact there's quite a few internationals at the beginning of June."
United's next match is away to Stoke City on Sunday, while City face Chelsea in the FA Cup semi-finals on the same day.