Long-time Chelsea team-mates Frank Lampard and John Terry have crossed paths before
While the players and supporters of Aston Villa and Derby County go through the ringer during Monday's Championship play-off final, Chelsea's past and, quite possibly, future will be taking more than a passing interest.
There's a Made in Chelsea feel to the Bank Holiday Monday Wembley fare, with Frank Lampard and Jody Morris in the Rams dugout and John Terry an assistant coach to one of Villa's own, Dean Smith.
On the pitch, youngsters Mason Mount, Fikayo Tomori and Tammy Abraham could well have a decisive say, while the not-so-young Blues legend Ashley Cole is also likely to be thrust back into the limelight.
BBC Sport looks at how the management dynamic is working out, as well as some of the key protagonists.
Rookie boss Lampard's appointment at Derby almost a year to the day raised more than a few eyebrows. But the 40-year-old has already shown there is more to him than simply being 'a name'.
Having been schooled by the vastly experienced Marcelo Bielsa in three out of three meetings with Leeds United, Derby then turned on the style to win a pulsating play-off semi-final second leg and secure their Wembley trip.
Lampard's player recruitment, man management and tactical nous has been widely praised and years of painful play-off misses for the Rams could be forgotten come Monday.
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But perhaps the shrewdest move of Lampard's short managerial career has been appointing Morris as his number two.
"It's Frank and Jody; it's an absolute team, which you see when you listen to them and see them together," former Chelsea and Scotland winger Pat Nevin told BBC Sport.
"Frank is the front man but you need the number two to be on equal footing with you.
"If people from the outside ask if Jody is a yes man then you just sort of laugh and say 'Really? Absolutely no chance'.
"Jody had a fantastic career but no one had a career like Frank so there could be a shadow there, but Jody is not bothered by that. His personality is huge. I worked with him for years at Chelsea and I have got to know the strength of his personality.
Former Chelsea under-18s coach Morris (right) made his Chelsea debut as a 17-year-old in 1996
"He will stand up for his own beliefs, but he will be incredibly respectful to Frank's beliefs as well.
"Frank's infamous niceness, which is absolutely his core personality, can be shoved too far and you will get the other side. Football is a really good mirror because you see the extremes of their personality.
"I have seen Frank lose it and react to people."
Jimmy Floyd Hasselbaink, who played with Terry, Lampard and Morris during a four-year stint with Chelsea from 2000, said at the time he didn't think Lampard would go into coaching.
"Obviously he has shown he can do that now," Hasselbaink told BBC Sport. "Back then he didn't have the same focus for it that you see with some players.
"But Frank and Jody were always very close and really good friends.
"Jody served his apprenticeship with the Chelsea Under-18s and had an incredible record there and Frank worked with them when he was doing his badges.
"The absolute trust is there and that is most important thing. The dynamics work."
But three's not a crowd
The dynamics seem spot on at both Pride Park and Villa Park - although the winning formula is slightly different.
Languishing 15th in the table when Dean Smith took over in October, the new boss brought in Terry as a coach alongside his tried-and-trusted deputy Richard O'Kelly, who Smith worked with at both Walsall and Brentford.
A slow start was followed by a club record 10 successive wins and an astonishing charge to the play-offs, before they went on to squeeze past West Bromwich Albion in the semi-finals.
Terry (right) was a player when Villa lost the 2018 play-off final against Fulham
Although Smith had never previously worked with Terry, one of his former team-mates and closest friends, Martin Ling, provided an unlikely link.
Ling, who played with Smith and then handed him his first coaching role at Orient, managed Terry's brother Paul.
"John would pop in for a coffee and I got to know him loosely," said Ling. "He was great and would chat to the younger lads. He is a class act.
"I spoke to Dean before he appointed John and John understands he is a learning coach and he does just want to learn. There is no side to John.
"I told him it was a total no-brainer. It has worked a treat and now they need to finish the job. But Richard O'Kelly should not be forgotten in all of this. He is an absolutely first-class coach."
'An extraordinary personality'
Pat Nevin said employing someone of Terry's stature as a number two did have an element of risk because he is a top-class manager in waiting.
"Your ears prick up slightly with that," explained Nevin. "Because if I had to pick anybody who I thought would be the best manager long term, I would say John Terry without taking a breath.
"You are bringing in somebody who has an extraordinary personality in the dressing room. I don't know if I have seen anybody better for the way he can motivate. And it's not just the shouting and bawling, it's every possible way.
"He has a fantastic knowledge and is incredibly hard working. People admire him and are awestruck by him, but also he puts people at ease.
"The time and effort he gives to people is extreme. He relaxes people and makes people comfortable and that is what has impressed me most.
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"I watched the way he worked with people at Chelsea, not doing it for show, but because that is what he does. He is like that.
"I am not painting him as angel because he has done things wrong. You think some of the criticism is deserved but most of it is probably not. The way that he is looked upon, the media have got it wrong. In 10 years he will be a fantastic manager.
"I have never seen someone better suited to be a manager."
But will Terry or Lampard, already recently linked with Chelsea, one day return to take the top job at Stamford Bridge?
"One of them will be manager of Chelsea one day, maybe two of them," said Nevin. "And it will be interesting to see who will be the first.
"That will be down to luck and getting the right job at the right time."
The next generation
Terry, Lampard, Morris and Derby's likely left-back for the day, Ashley Cole, have 1,878 Chelsea appearances and 294 goals between them from a combined 49 years of service with the club.
The next generation of Mount, Tomori and Abraham have played just four times for the Blues first team.
Nevin said those numbers could well rise, particularly if the Fifa transfer ban comes into force at Chelsea this summer.
"Mason Mount has been immense for Derby," added Nevin. "Frank asks him to do different things. You cannot just do the one thing as a midfielder; you need to adapt and he has shown brilliant adaptability.
"He creates and brings goals, but then at other times he can do the rough stuff. He is not the best tackler in the world but he is good enough. He has the all-round ability."
Tomori is likely to be directly up against 26-goal Abraham - a contest Nevin believes will be vital on Monday.
Will Tomori and Abraham, pictured here in a rare 2016 outing, ever go back to Chelsea?
"I have watched a lot of Chelsea youth development football and Tammy has always been the one that I thought could make the breakthrough," said Nevin.
"He has a really good chance to make it at Chelsea - just when it will be I don't know. I would like to see him back there next season but only if he is getting games. If not then he should stay at Aston Villa."
Before then, Monday looms into focus. Villa may have the edge having twice thumped Derby in the league this season but the Rams recovered from three defeats against Leeds to win the game that really mattered to reach Wembley.
"JT and Frank both have that credibility with the players to start with," said Hasselbaink. "They have been there and done it and when they talk young players and experienced players listen.
"They have achieved so much. They know how to cope with the stress. Play-off matches are huge and they can help the players deal with the stress in the big moments."