Shinji Kagawa has revealed he was shocked by the force of Sir Alex Ferguson's famous "hairdryer" tactic at Manchester United.
Former United manager Ferguson had a well-documented policy of shouting directly in players' faces when he was angry.
And Japan international Kagawa, who joined the Red Devils from Borussia Dortmund in 2012 and played in Ferguson's final season in charge, was astonished to see the Scot using it to galvanise his senior players.
"Although I had heard about the [hairdryer] rumour before going to Manchester, I hadn't seen any managers shouting that hard," Kagawa told reporters.
"It really was like a hairdryer, as it is called. He shouted really hard with his face really red, especially at the core players."
Kagawa said he was spared the worst of Ferguson's more brutal "hairdryer" tactics but believed they were very effective.
"It was my first season, so he maybe overlooked me a little bit and I didn't get shouted at very much," he said. "The fact that he can shout at leading players such as [Wayne] Rooney, [Ryan] Giggs, [Paul] Scholes, Rio [Ferdinand] shows his presence.
"Those players have to take it in and cannot say anything, so the players respect him that much. His aura and his driving force are really great and I thought that's why he had the ability to manage those players."
Kagawa returned to Dortmund from United when current boss Louis van Gaal sold him in 2014.
However, he said he regards it as a major honour to have played for Ferguson, who won 13 league titles and two Champions Leagues during his 27-year stay at Old Trafford.
"I think it was a great experience for my football life that I played his last season with him, someone who has the greatest number of titles in football and is a legendary manager," Kagawa said. "It really was a big moment to be with that kind of person."