The Pep Guardiola and Jose Mourinho rivalry in the early 2010s was truly epic.While they were in charge of Barcelona and Real Madrid respectively, the two managerial greats engaged in some heated battles - both on and off the pitch.Their press conferences were pure box office and the El Clasico fixtures with those two in the dugouts were ridiculously entertaining.The fact Lionel Messi and Cristiano Ronaldo came face-to-face in the games also added an enormous amount to the occasion.But while the rivalry was great for the fans, Gerard Pique believes it ultimately had a detrimental effect on Guardiola.By 2012, just two years after Mourinho arrived in Spain, the current Manchester City boss left Barcelona.When speaking to Gary Neville on The Overlap, Pique claimed that Mourinho's off-field antics were simply "too much" for Guardiola.
Video: Pique's thoughts on Guardiola vs Mourinho
The Spaniard said: "We were winning everything at the time and I remember the first time Mourinho came to the Camp Nou he lost 5-0 against us.
"It was a shock of reality of 'woah, these guys go hard'. Mourinho in the press conference, he was every day... you know his style. I think Guardiola at some point, it was too much. It was more important what was happening off the pitch instead of on it.
"I remember at the end of the day, Guardiola left, Mourinho had won the league that year, and all of a sudden he decided to leave. I'm sure part of it is, with Mourinho, it was too much."
Interesting. During Barcelona and Real Madrid's spectacular Champions League semi-final tie in 2010/11, Guardiola gave what Pique referred to as an "amazing press conference".
However, the Barcelona defender believes it was the moment that it all stopped being about the football.
MADRID, SPAIN - APRIL 27: Jose Mourinho the coach of Real Madrid and Pep Guardiola the coach of Barcelona shake hands prior to the UEFA Champions League Semi Final first leg match between Real Madrid and Barcelona at Estadio Santiago Bernabeu on April 27, 2011 in Madrid, Spain. (Photo by Alex Livesey/Getty Images)
Pique says it "stopped being about football"
"I remember the semi-final of the Champions League in the Bernabeu, he did an amazing press conference but it was not about football," the 35-year-old star continued.
"He enjoys talking about what is happening on the pitch and here, there was a moment where the press conference was focusing on what was happening outside the pitch."
Guardiola tried to outwit the master of mental mind games that is Mourinho, a road he probably should not have gone down in hindsight.
Pique also revealed in his interview with Neville that Mourinho turned Real Madrid's Spanish players against their countrymen that played for Barcelona.
VALENCIA, SPAIN - MAY 11: Head Coach Josep Guardiola (L) of Barcelona gives instructions to Gerard Pique during the La Liga match between Levante UD and Barcelona at Ciutat de Valencia on May 11, 2011 in Valencia, Spain. The match ended 1-1. (Photo by Manuel Queimadelos Alonso/Getty Images)
Mourinho's mind games impacted Spain national team
Pique added: "Since he arrived, he knew that on the pitch they were weaker than us. We had a better team for sure, and even the relationships between players.
"I remember going to the national team and after those games it was tough because Mourinho goes to the mind of the player and he says ‘these guys hate you’, then you believe that.
"I was in the dressing room of the national team and went to Iker Casillas 'hey Iker' and the guy did not talk to me.
"At that time I did not know, but it was the coach he really knows how to go into the mind."
Spain went on to win Euro 2012, though, so things can't have been that bad behind-the-scenes...