Chelsea were a powerful force to be reckoned with under Jose Mourinho, Carlo Ancelotti and many more managers they had between 2004 and 2014, with training ground fights a regular occurence.
Though they were often winning Premier League titles, FA Cups and even the Champions League, things weren't always harmonious between Chelsea team-mates during their successful era.
As John Obi-Mikel reveals, tensions would often boil over during training sessions as the competitive Chelsea squad constantly strived for greatness on the pitch. Mikel himself had a fight with one member of the side, while also recalling a knockout blow landed in one of the scraps.
Chelsea players regularly had fights in training
"There were real, proper fights during training," Mikel told the High Performance Podcast. "I remember Michael Ballack had a fight with Salomon Kalou. Salomon Kalou was a very quiet guy, lovely boy, but Michael Ballack must have done something [to him] that day. He went off.
"We don't know what happened but Michael Ballack must have done something that's got Salomon Kalou to go off. Proper fight. They had to be separated, had to be pulled away."
The most controversial of all fights came when Andriy Shevchenko reportedly landed a knockout blow on defender Tal Ben Haim, though.
"There were so many fights," Mikel said. "I remember one with Tal Ben Haim and Andriy Shevchenko, but I think Tal Ben Haim got knocked out properly.
"Again, [Shevchenko was] somebody who never spoke. You would never hear Shevchenko say a word, but it just shows the competitiveness."
Mikel himself wasn't shy of getting involved, either, with the Nigerian recalling how players intentionally set up situations to allow a heavy challenge to fly in during rondo exercises.
"When you give a bad pass, sometimes you're trying to set someone up to get smashed," he added. "Florent Malouda spoke French, I think to Didier Drogba, and said 'give him a short pass because I want to smash him'.
"So Didier laid a short pass and I went for it and got absolutely hammered. I jumped up and we both went at it. Carlo Ancelotti was standing there and he rushed in and we got separated."
