Pep Guardiola and Ralf Rangnick have had vastly different careers and if we were to compare their trophy cabinets let's just say it would be a little one-sided.
But they are both hugely influential figures, having made their mark on football in Germany and abroad.
However, today's derby between Manchester City and Manchester United will be the first time the two coaches will have met each other in a match.
Rangnick has been a coach for 39 years, starting his career in the dugout all the way back in 1983 with hometown club Viktoria Backnang, when Guardiola was only 12 years old and hadn't even joined Barcelona's youth academy.
While Guardiola made his name as the midfield boss of Barcelona's 'Dream Team' under Johan Cruyff and then went on to become one of the most successful and admired managers of all time, Rangnick had a very different path to coaching stardom.
He made his name via a television interview with German show ZDF Sportstudio, presenting his ideas on pressing in a 1998 episode with host Michael Steinbrecher.
Rangnick was then in charge of second-tier leaders SSV Ulm 1846 and his appearance on the show gained him huge admiration among the upper echelon of German football and a year later he got his first job in the Bundesliga with Stuttgart.
He later worked for Hannover, Hoffenheim and had two stints at Schalke in the top-flight but by the time Guardiola arrived at Bayern Munich in 2013, Rangnick had transitioned from coaching to sporting director with the Red Bull group, working with New York Red Bulls and RB Leipzig.
He became coach of Leipzig in 2015 and propelled them to their first promotion to the Bundesliga the following season but he then resigned from the role, with Ralph Hasenhuttl taking charge of their debut campaign in the top flight.
By then, Guardiola had left Bayern after winning three successive Bundesliga titles and was heading to City.
What does Guardiola think of Rangnick?
Although his teams play in a very different way to Rangnick's sides, pressing has always been central to Guardiola's style of play.
And he was highly complimentary of the German ahead of their first meeting on Sunday at the Etihad.
"I would say the idea from Ralf Rangnick is the tendency already in the Premier League," Guardiola said.
"So many teams want to play in this way. Ralf Rangnick is like the father of the gegenpress or these transitions.
"We see that with Liverpool, Southampton Liverpool, Southampton and with Jesse Marsch now at Leeds, a little bit with Chelsea and Thomas Tuchel, although Thomas Tuchel plays a little bit wider with wing-backs. But it is the tendency.
"Most of the clubs who are already here in England are playing this way, and important ones. Five or six teams are playing in this way. The work he has done in Germany is exceptional.
"In Leipzig, he created a proper school. From Austria and New York, all the teams play the same way."
"The best team in the world"
Rangnick also heaped praise on his opposite number, hailing Guardiola's impact at every club he has worked for.
"We know that we are playing one of, if not the best team in the world," Rangnick. said.
"They have developed well since Pep arrived.
"The same happened at Bayern Munich and Barcelona. He is one of the best."
