In his new autobiography published this week, Republic of Ireland and Aston Villa assistant manager Roy Keane finds space during his forensic analysis of his career and former colleagues to call the motivational powers of ABBA's music into question.
The Guardian reports that while writing about his time as Sunderland manager in The Second Half, Keane says: "It might seem strange but you find out about characters when you look to see who's in charge of the music [in the dressing room].
"A young lad might want to put on the latest sound; an older player might say: 'I'm the senior player' and put himself in charge."
Keane continues: "But I noticed none of the players [at Sunderland] were in charge of the music and this was a concern for me. A member of staff was in charge.
"I was looking at him thinking, 'I hope someone nails him here'. The last song before the players went on to the pitch was Dancing Queen by ABBA."
He adds: "What really worried me was that none of the players – not one – said: 'Get that **** off'. They were going out to play a match, men versus men, testosterone levels were high. You've got to hit people at pace. ******* Dancing Queen. It worried me. I didn't have as many leaders as I thought."