Former Wales fitness coach Ray Verheijen has criticised Manchester City boss Pep Guardiola.
City's 4-0 hammering at Barcelona on Wednesday extended their winless run to four matches.
Verheijen said: “Tactical teachers often have a poor injury record.
“You can see Manchester City are already dropping and accumulating fatigue and players are picking up muscle injuries. Now you can see the performances are starting to dip.
“The patterns of his past are starting to develop again."
He added: “Pep went to Bayern and the players were totally unfamiliar with his playing style and tactics.
“When he was coaching at Barcelona, most of his players came from the academy so they were familiar with the style and he didn't have to do much tactical training.
“But at Bayern he had to start from scratch. He had to do much more training to teach them the playing style. He over-trained the players. This is not an opinion — these are facts.
"People should not argue with me. Pep Guardiola's injury record at Bayern Munich is a fact.
“Before Guardiola went there, the Uefa injury study by Professor Jan Ekstrand showed Bayern were No1 in terms of the best injury record in Europe for Champions League teams.
“When Guardiola arrived Bayern dropped dramatically and became one of the worst during those three years."