City’s preparations ahead of Saturday's clash have been disrupted by injuries to a host of defenders, with the likes of Aleksandar Kolarov, Micah Richards and Wayne Bridge all ruled out, whilst Joleon Lescott and Jerome Boateng are both doubtful.
This isn’t the first time that such an accusation has been levelled at the former Inter manager. Just last season Carlos Tevez and Craig Bellamy, now on loan at Cardiff City, both hit out at Mancini’s training methods.
Verheijen, the club’s former conditioning expert, who worked under Mancini during the beginning of his reign at Eastlands, has launched a scathing attack on the City manager, citing him as the main reason for the enormous amount of injuries at Manchester City, whilst then going on to say how he hopes that Mancini will "finally question his training methods".
The Dutchman is a respected figure in the game and has a vast amount of experience at the highest level, recently accompanying the South Korean team to the World Cup as performance manager, whilst he has also worked for both the Russian and Dutch national teams and has also been employed by Spanish giants Barcelona.
"I really feel sorry for [the] Man City players. They are having a difficult time. Hopefully none of them will suffer a career threatening injury," Verheijen wrote on his Twitter page.
His criticism follows revelations about his initial misgivings of the Mancini regime, which were published in the latest edition of 'FC Business', the trade magazine for the football industry.
In the interview Verheijen states his beliefs that whilst under the management of Mark Hughes, City were "the fittest team in the best league in the world".
The former City employee credits the player's excellent fitness levels at the time to the way Hughes and his backroom staff spared them unnecessary long runs and double sessions in pre-season training.
"During pre-season and the first half of last season Mark Hughes had all his players available," Verheijen said.
"City played each game with the same team. The team had the best Prozone [computer data] statistics of the Premier League during the first part of the season.
“The players had the highest number of sprints and the highest total sprinting distance of all the Premier League teams.
"After the arrival of Mancini things changed dramatically. He probably did not even look at the Prozone statistics and our best-injury record in the Premier League.
“He decided players had to do double sessions many times a week. Those sessions often lasted for two hours. Not surprisingly the players picked up eight soft-tissue injuries within the first two weeks of Mancini."
The Dutch coach continued by then moving onto the millions of pounds Mancini has lost the club.
"The benefits for the clubs are quite clear. Less injuries mean less money lost. In modern football lots of money is still lost because of the methods of coaches. Manchester City is the perfect example.
"In the second half of last season City had a dreadful injury record which has cost the club an enormous lot of money. Club directors should be aware that 90% of injuries in football can be avoided. They should raise the bar within their organisation to demand more professional training methods."
Manchester City have since reacted to Verheijen’s claims and were quick to attribute his explosive allegations against Mancini as a reaction to his recent departure at Eastlands.
"Mr Verheijen appears to have become a regular critic of Roberto Mancini's training methods, perhaps not entirely coincidentally since his consultancy services at Manchester City were terminated by the club several months ago. We wish him well in his future practice,” a club spokesmen said.