The Spaniard joined the Club last summer, adding a wealth of coaching experience to our already impressive backroom team.
His relationship with Guardiola goes back to the boss’ playing days, when he finished his career under his assistant’s watchful eye at Mexican outfit Dorados de Sinaloa in 2006.
And speaking in his pre-match press conference ahead of Friday’s trip to Newcastle, the City boss insisted that Lillo’s unique qualities have made a massive impact this campaign.
“Juanma is a friend from a long time ago. I went to Mexico to train with him, I learned a lot from him when I played,” Guardiola reflected.
"He sees things I am not able to see and especially has something so important for me, he is an incredible optimist.
“Secondly, he never speaks bad about another person. Never.
“Normally in groups when you don't win, you find excuses to say bad things. Juanma is the opposite. He always sees the best things in people, positive skills in the player.
“In bad moments, he always finds how the good is going to come in the next weeks and the next months.
"When you are the manager you have a lot of pressure and Juanma helps me a lot, he says the right words at the right time to me and the players sometimes.”
NEWCASTLE V CITY
We will have full coverage of Friday's game right here on ManCity.com
Live text updates in our Matchday Centre will begin at 18:00.
And our We're Not Really Here studio show starts at 18:55. Kevin Horlock and Gareth Taylor are our guests for this one.
Short highlights are available from midnight - and CITY+ subscribers can also watch a full 90-minute replay from midnight.