Germany vs USA: Now the two coaches face off at Recife's Arena Pernambuco as rivals with both teams on four points.
Friends clash on either side of the World Cup divide on Thursday when Jurgen Klinsmann's United States meet Joachim Loew's Germany for top spot in Group G.
Having met on a coaching course, Loew became Klinsmann's assistant a decade ago when the pair were brought in following the Euro 2004 debacle as Germany finished the group stages winless.
Under their stewardship, Germany became known for fast-paced attacking football as talented youngsters such as Lukas Podolski and Bastian Schweinsteiger were given their chance.
The pair took Germany to third at the 2006 World Cup before Klinsmann stood down as coach to be replaced by Loew, who has since steered them to at least the semi-finals of the last three major tournaments.
Now they face off at Recife's Arena Pernambuco as rivals with both teams on four points.
A mutually beneficial draw would see Germany qualify as group winners with the United States runners up, knocking out Ghana and Portugal.
That scenario has brought back memories of a notorious 1982 group match in Spain -- dubbed the 'Disgrace of Gijon' -- between West Germany and Austria. Both qualified at the expense of Algeria after a 1-0 German victory as the teams went through the motions -- something both sides insist will not happen in Recife.
"That is only a part of Germany's history and not part of the United States' history. I think if you look at the past of the US team, we always try to make things happen," said Klinsmann.
Klinsmann insisted the United States will go all out for victory while he remains a Germany fan and so he will sing both national anthems with gusto.
He has four Bundesliga players in his USA squad, while Jermaine Jones won three caps for Germany before switching allegiances in 2009.
Klinsmann's special advisor is Berti Vogts, who coached Germany at the 1996 European Championship when former striker 'Klinsi' captained the side to the title.
'Germany can be world champions'
"This game is something quite special for me, something like this comes along perhaps once in a lifetime," said Germany's former 1990 World Cup winner Klinsmann.
Despite having lived on California's Huntington Beach for the last 16 years with his family -- his son Jonathan is a goalkeeper for the US Under-18 team -- Klinsmann remains loyal to his roots.
"Germany has enough potential to become world champions and when the 90 minutes are over, I'll be keeping my fingers crossed for them," he said.
"This generation of players only needs to put the icing on the cake.
"I have worked with most of these boys, always followed their careers and hope that they achieve the crowning success. Previously there has always been something missing, I hope they achieve it this time."
But the fact that his former head coach will be on the opposing bench is of little concern to Germany captain Philipp Lahm.
"That is a theme for the media, not the players," said Lahm, who was part of the Germany team which reached the semi-finals in 2006 and 2010.
"We had a super time working together, but that is a few years ago, this is all about reaching the last 16 for us now."
While Loew and Klinsmann remain close friends, contact has been kept to a minimum as they go about their respective World Cup business.
Klinsmann had the last laugh when the USA shocked Loew's Germany 4-3 in a Washington DC friendly last June when the weakened Germans suffered only their third defeat to the Americans in nine meetings.
Loew said normal contact will be resumed with Klinsmann only after the tournament.
"It's obvious that we've had no contact recently, that's normal in such tournaments where you sometimes bump into each other," said Loew.
Klinsmann certainly has big plans for his side with his flight home from Brazil 2014 booked for July 15 -- two days after the final.