Later that year, with Liverpool toiling in the league, Rodgers looked to Guardiola for ideas again.
Adopting the 3-4-2-1 playing system that Guardiola had introduced at Bayern, Rodgers inspired his team to a run of 10 wins and three draws that rejuvenated their season.
Rodgers’s commitment to passing football has not gone unnoticed by Guardiola.
“I don’t think there is any doubt about Brendan’s quality,” the City manager said last month.
“He was closer than anyone in the last 25 years to winning the Premier League at Liverpool and he has a lot of experience.”
Guardiola, 45, has been praised for revitalising Raheem Sterling this season, but the England winger also remains grateful for the guidance he was given by Rodgers during their three years at Liverpool.
“He was massive for me,” Sterling said this week.
“Every manager that I’ve worked with, I’ve tried to learn as much as I can, and he’s one that I definitely learnt a lot off. Credit to him, he was a fantastic guy.
“Playing me in different positions, making me understand the roles and maturing in certain systems. He gave me a lot of confidence as well.”
Looking to rebuild his reputation at Celtic after being sacked by Liverpool a year ago, Rodgers saw his new side dealt a humiliating 7-0 defeat by Barcelona on their opening Group C outing.
At Glasgow’s Celtic Park on Wednesday, against the man who laid the foundations for the present-day Barcelona, Rodgers has another chance to prove all those years of Spanish homework were not in vain.