Arsenal manager Mikel Arteta hailed Mauricio Pochettino as a "big brother" and believes he is already turning things around at Chelsea.
The pair played together for a year at Paris St Germain, both arriving in 2001 and striking up a friendship that lasts until the present day.
They have since gone on to become top coaches - but their meeting at Stamford Bridge on Saturday will be the first time they have faced off as opposing managers.
Pochettino, 51, is 10 years older than Arteta and while they may have signed for PSG at the same time, the Arsenal boss credits the Argentinian for taking him under his wing.
"First of all, it was my first professional opportunity in Paris and we arrived at the same time and lived together in a hotel for three months," Arteta explained.
"He was critical, has been one of the most influential people in my career. Firstly as a player, he took me under the arm and looked after me like a little child, a little brother, and he was a big part of the success I had in Paris.
"It was because of him because he really looked after me, gave me a lot of confidence and a lot of advice.
"He has been a role model for me since that day, not only when I was a player but as a manager as well, when I had to make the decision to leave playing and start my coaching career he had a big say on that and I will always be grateful."
Arteta has been in charge of Arsenal since December 2019, just a month after Pochettino was sacked as head coach at north London rivals Tottenham.
Pochettino returned to the Premier League when he took the reins at Chelsea in May and, despite a turbulent start, Arteta feels his old colleague is starting to turn things around.
Asked if he felt Pochettino could rise to the challenge, he replied: "Yes, you can see already that something has changed very quickly.
"It's a big game and there is a big history between the two clubs. We know the types of games we've played together with them in the past but this is a different one. I've been really impressed by Chelsea.
"I think they deserve much more than what they've got in the table. What Mauricio has done in a short time is phenomenal. We'll be have to be at our best."
Arteta also revealed the best advice Pochettino had offered after he had hung up his boots: "'Don't go into coaching - it's too hard'!
"That is the first thing. I knew he was going to be a coach and I followed him very closely because as a player he was already a leader.
"The way he understood the game was phenomenal. I used to have him at my back and he was constantly coaching me. Very proud of what he has done and the way he has done it through his coaching career."
Arteta's kind words were returned by Pochettino in his own press conference, during which he called the Spaniard "one of the best in the world".
"We respect Arsenal, they are a great team," Pochettino said.
"They have Mikel (Arteta) who is part of my family. It's going to be tough because they’re doing a great job with a great squad, they are a contender to win everything, the Premier League and the Champions League.
"It does not surprise me with what he’s doing. He’s great, he’s really young, he’s improving every day and he can be one of the greatest managers in the world. I’m going to be proud to see him.
"I think when you are a coach at Arsenal and the team is showing what they are showing it’s because you are one of the best."
