Jurgen Klopp and Antonio Conte are both renowned for their stringent and intense approaches to management.
While their methods often get results, there is also the much higher risk of injuries, particularly in the most congested parts of the domestic campaign.
Pre-season is often the most gruelling and arduous period in the footballing calendar and while Liverpool and Chelsea's players adjust to the heavy workload their managers put on them at this stage of the campaign, one man has heavily criticised Klopp and Conte's practices.
Raymond Verheijen was Gary Speed's assistant manager for Wales and he thinks the two aforementioned managers are using outdated methods which can 'destroy players'.
He posted a series of Tweets (see below) to explain the dangers of double and triple sessions at this early stage of the campaign.
Verheijen went on to add that players are overworked and has a three-phase theory to describe and predict what will happen over the next few weeks, with the Premier League opening fixtures now less than a week away.
Now you would be completely right to have reservations regarding the Dutch coach's wild accusations, however he does have a bit of a track record.
Just last year, the 44-year-old correctly predicted that Liverpool would suffer an injury crisis in January and once again criticised Klopp's methods.
Conte and Klopp are still relatively inexperienced in English football and the lack of a winter break in the Premier League could certainly play a factor in their injury records this season. Both the Bundesliga and Serie A have extended breaks over Christmas to allow the players to recuperate - a luxury not on offer in England.
Liverpool are already having an injury crisis of sorts after Joel Matip limped off during their latest pre-season friendly against Wigan - joining Mamadou Sakho and Joe Gomez on the sidelines and leaving their defence looking threadbare with the upcoming season rapidly approaching.
Although Klopp and Conte are expected to remain stubborn to their tried and tested strategies, the managerial pair may want to take Verheijen's comments far more seriously if they are forced to prematurely throw in some of their clubs' youngsters to make up the numbers during the festive period.