The toughness and guile that made Diego Simeone a great player has been there for all to see in his time as manager of Atletico Madrid, and the Argentinian marks his 300th game at the club with a major challenge on Sunday against Barcelona.
Simeone's team has yet to beat Barca in domestic competition, but they broke the 10-year duopoly of Barcelona and Real Madrid in La Liga in the 2013-14 campaign - the club's first league crown for 18 years.
Atletico had won only two trophies in the 15 years before Simeone's arrival and since he became manager in 2011 the outfit has won five.
He has also steered the club to titles in the Europa League, UEFA Super Cup, King's Cup and Spanish Super Cup, and has presided over two home victories over Barcelona in the last three seasons to reach the Champions League semifinals.
But Barca has lost all 16 domestic matches.
The club did however win La Liga with a 1-1 draw against Barca, arguably Simeone's greatest accomplishment, and they have won 187, drawn 61 and lost 51 of 299 games with him in charge.
Barcelona, yet to get over losing 4-0 at Paris Saint Germain in the Champions League last week, were not convincing in the game that followed, a 2-1 home victory over Leganes following a 90th minute Lionel Messi penalty.
Atletico have, meanwhile, hit their stride, winning 4-1 at Sporting Gijon and then going on a scoring rampage at Bayer Leverkusen to win 4-2 this week.
Atletico fans - now with 100,000 members for the first time in their 113-year history - will be rooting for Simeone at the Vincente Calderon stadium because this is likely to be his last chance to do so at the venue with the club moving next season.
"The family doesn't stop growing, congratulations," Simeone said on Twitter, referring to the membership milestone.