Twenty-eight years later, their bond is only deeper even as they face off in a Division Series between the Red Sox and the Indians.
Prior to tonight's Game 1 (8 p.m. ET, TBS), when Francona is announced during pregame intros, he will reach over to the third-base side of home plate and greet his good friend.
Whichever manager wins this series isn't going to feel good about the pain the other one will endure.
"And it's tough when you're going to compete against one of your best friends. That's actually kind of hard, but I am so proud of him and happy for him, what he's accomplished," said Francona, who managed the Red Sox from 2004-11. "I kind of consider it an honor to actually compete against him."
They made it to the postseason for three of the four years (2007-10) they were together in Boston -- Francona as manager and Farrell as the pitching coach. As a tandem, they basked in World Series championship glory -- eliminating the Indians along the way -- in 2007. When Francona won the AL Manager of the Year Award in '13, Farrell finished second. That same year, Farrell's Red Sox won the World Series.
But their relationship has long transcended the game they love. When Farrell underwent his first chemotherapy treatment last August for Burkitt lymphoma, the Indians happened to be in Boston. Francona accompanied him for the daunting experience, keeping him loose with humor and making sure Farrell knew he was there for him.
• Castrovince: CLE-BOS connections more than Tito
"We've shared a lot of personal things," said Farrell. "Whether it's health, off-the-field situations, in addition to the professional side of things. He's been a great friend. He has been very open and helpful when talking through certain situations. He's always been someone to lean on."
Farrell has made his share of friends during his time in baseball, but it's safe to say where Francona ranks among them.
"He's at the top of it because of so many things that we've shared as teammates and on the same staff," said Farrell. "He's a great manager, and it would be crazy not to reach out to him when certain situations arise. I think, more than anything, if you're ever in need, it's always a phone call that will be taken and he'll help you in any way possible."
Francona and Farrell are the only Boston managers who have won World Series championships since 1918. Boston is a market that can carve a manager up with scrutiny, and Farrell had the advantage of watching how Francona handled every situation for four years.
What were Farrell's biggest takeaways from Francona?
"The way he dealt with the different personalities here. The way that he would pre-empt any situation that might become a big story in the media," said Farrell. "His ability to contain that from maybe growing into a bigger issue than it was. So his ability to manage a clubhouse, manage individual personalities and so many different types that were here during the four years together. He was a master at that.
"And then the trust that he puts in players. He never forgot how difficult the game is. And whether that was with players who might be going through a period of at-bats where there might be scuffling a little bit to understanding usage of a bullpen and how the confidence of a given reliever can be built and brought along."
The similarity between the managers is clear from the way they've answered questions about matching up with each other in this series.
"This game is still always about the players, and will always be," said Farrell.
"The one thing I think I need to be cognizant of is the players have worked so hard on both sides to get to this," said Francona. "I can't let my personal feelings ever get in the way or take away from what they've done. So, whatever my feelings are need to remain my feelings, and let the players have the spotlight. They've worked so hard for this. It needs to be about them."
While Francona and Farrell have similar values when it comes to leading a team, their difference in temperament is apparent to those who have played for them both.
"Tito jokes around a lot," said Red Sox second baseman Dustin Pedroia. "When the game starts, John doesn't joke around. There's not one way to be successful. Obviously John learned a lot from Tito when he was under him. There's a communication level that he learned from Tito that he carried forward."
For the next week or so, the friendship will take a backseat to the competition. But no matter how the series goes, it will be business as usual for the two men after that.
"I cherish my friendship with him, to the point where you confide in one another, even in the darkest moments during stretches of the season where things aren't going well," Farrell said. "I can't say enough about the guy. I've spent a lot of time with him in many different settings. I have a tremendous amount of respect for him, and the teams he puts together. But we'll have time for friendship later."