Emma Hayes has revealed she ditched a chat with Mauricio Pochettino to take a call with former Manchester United manager Sir Alex Ferguson.
Ferguson called the Chelsea women's boss after it was announced she would be leaving the club after 12 years.
Hayes will depart at the end of the season to become manager of the United States women's national team.
"We had a chat last week, he rang me, but I was in the middle of talking to Poch so I was torn," Hayes said.
The 47-year-old said she had to tell Chelsea men's manger Mauricio Pochettino to wait: "There's not many people you tell Poch to wait for but I did say to him it was Sir Alex."
Hayes, who has guided Chelsea to 13 major trophies since joining the club in 2012, added: "He calls me from time to time so I wasn't surprised."
Ferguson won 13 Premier League titles, five FA Cups, four League Cups, two Champions Leagues, a European Cup Winners' Cup, a European Super Cup, an Intercontinental Cup and a Fifa Club World Cup during his time at Manchester United.
"Anything he says to me I always take with such pride. He is a legend of the game and someone whose opinion I value and he has a love of America," Hayes said.
"We talked a little bit about that, a little bit about legacy, a little bit about leaving at the top. So there were wise words from him. I'm sure it won't be the last phone call I get from him this season."
'My family are devastated'
Hayes said part of her decision to leave Chelsea was because she did not want to overstay her welcome, but she says her departure will cause her family some upset.
"My family are devastated - they are Chelsea," Hayes said.
"It's not every day that opportunity is going to come up in life and I never saw it coming, I never thought it was necessarily something I was going to do.
"The timing and the opportunity is never going to come around again, plus where I am with everything in life, plus not wanting to outstay my welcome. It's all of those things that were the deciding factors."
Chelsea host Liverpool in the Women's Super League at Stamford Bridge on Saturday (13:30 GMT, BBC One), and Hayes says she will cherish every moment with the club's fans until she leaves.
"I feel guilty, I feel like I'm abandoning my family. It's in my heart. Any moment I have with the fans I always enjoy, but every moment I have with them until the end will feel special," she said.
"I've given fans and the community a team that people can identify with, and they can enjoy watching. I'm not done yet, there's a lot of winning to do this year."