My friend Joey Barton says psychology is a huge part of what it means to be a coach. He's completely right, and in researching my Lionel Messi book, I've come upon some fascinating stories to shed light on the mind games managers play.
There are three examples in particular I want to share with you.
Henk ten Cate was Barcelona's assistant coach during the successes of Frank Rijkaard at Camp Nou (two La Liga titles and a Champions League trophy between 2003 and 2006). When I spoke to him recently, he revealed a tactic they employed with Edgar Davids, the Dutch international midfielder.
Ten Cate used Davids, an established player with a fierce work ethic, to test other players in training. Communicating with him by text message, he'd ask Davids to go hard on one player, or provoke and have a go at another player.
It was a way for ten Cate to check up on his players and see how they'd react. In some cases, Davids played along so well he was kicked out of training.
Ten Cate was a master of this type of thing.
The next story comes from a conversation I had with Leeds United manager Brian McDermott. He told me he and his staff have taken to a fitness program called "Iron Man," in an attempt to get fitter and thinner.
The rationale behind this is simple: McDermott wants to be seen by his players to be working as hard as they do. He believes projecting the right image lends itself to greater authority and the ability to assert greater demands on his team.
Sir Alex Ferguson applied this logic to the long hours he worked at Manchester United. Which leads me to my third example of how psychology plays a role in management.
McDermott told me Ferguson once asked him to share a cup of tea before a game against Manchester United. It was an unusual move, and my suspicion is that Ferguson was trying to relax his opposition manager and dilute some of his competitive juices before the game.
It's also interesting how Ferguson approached his potential successors at Old Trafford. I have it on good authority he wasn't considering Jose Mourinho, but he was more than happy for Mourinho to think he was in the running.
As Pep Guardiola has relayed to me, Ferguson met privately with him and the pair exchanged emails. Again he was happy for Guardiola to think he had a chance of getting the job.
And, as mentioned by The Guardian's Daniel Taylor, one night out the blue, Ferguson invited David Moyes and his wife over to dinner.
"I'm retiring," he told Moyes. "You're the next Manchester United manager."
The lesson here: We should never underestimate the role of psychology in being a coach.