Pep Guardiola and Jorge Sampaoli will attempt to bounce back from chastening Champions League defeats on Sunday against opponents unlikely to do them any favours.
Guardiola's Manchester City and Sampaoli's Sevilla went into the second legs of respective last-16 meetings against Monaco and Leicester City leading the ties and dreaming of making an impression at the business end of the competition.
However, Leonardo Jardim's swashbuckling Monaco and a stunningly revitalised Leicester had other ideas and Liverpool and Atletico Madrid will aim to pounce upon demoralised familiar foes on Sunday.
These were setbacks for two coaches chasing another addition to glittering CVs; men who have reached the elite via contrasting paths, but who share a common mentor and playing style.
"When I was younger I went jogging wearing headphones on - not for music, but for his press conferences," Sampaoli once said of Marcelo Bielsa, his predecessor as Chile boss, fellow Argentine and guiding inspiration.
A fanatical tactical innovator, affectionately dubbed "El Loco", Biesla will return to top-level coaching with Lille in Ligue 1 next season. The influence of his high-tempo passing style, with fluid transitions from defence to attack, tireless pressing and diligent positional play, remains strong among devotees.
"My admiration for Marcelo Bielsa is huge because he makes the players much, much better," said Guardiola of the genial 61-year-old, whose advice he sought before launching a coaching career. "For me, he is the best coach in the world."
Guardiola is primarily a disciple of the late, great Johan Cruyff, but described his Barcelona side's 2-2 draw at Bielsa's Athletic Bilbao in 2011 as an "ode to football" - a label that could easily have been applied to a second European Cup final triumph over Manchester United in three seasons earlier that year. His stock had never been higher.
At the end of 2012, Sampaoli replaced Claudio Borghi as Chile boss and set about restoring and building upon La Roja's Bielsa legacy. They dumped Spain out of the 2014 World Cup, ending the dominance of the international game of a team with Guardiola's Barca at its core, before winning a first major honour at the 2015 Copa America.
Throw in Guardiola's successful implementation of his style at Bayern Munich and its resulting influence upon Germany's 2014 World Cup win and the prints of "Bielsista" were in all the right places.
Fast-forward to the present day and we find Manchester City manager Guardiola 13 points behind runaway Premier League leaders Chelsea, helmed by Antonio Conte, who landed the final crushing blow against Spain's imperial phase at Euro 2016 - a tournament won by Fernando Santos' ultra-defensive Portugal.
Over in LaLiga, Catalunya Radio reported this week that Sampaoli was no longer in the frame to succeed Luis Enrique at Barcelona. The historic comeback to down Paris Saint-Germain has seemingly convinced the Camp Nou hierarchy that a radical change is not necessary.
Sampaoli and his assistant Juanma Lillo - one of Guardiola's great friends and confidants - would arguably add embellishment that is unwanted within a Barca side reliant more on superstar forwards than tactical trickery, much like fellow European heavyweights Bayern and Real Madrid.
Sevilla are winless in three before facing an Atletico side they are seeking to usurp as best-of-the-rest in Spain this year. Atletico boss Diego Simeone has provided a crunching counterpoint to football's more hipster tendencies in the current decade.
Barcelona could not beat Atletico across six attempts during 2013-14, when the capital club sensationally claimed the LaLiga title. The manner of that against-the-odds triumph was frequently cited as evidence that Leicester could do the impossible in England last season. They did, with a style Sampaoli found to be stubbornly effective this week.
Simeone's men also gritted their way past Guardiola's Bayern in the Champions League semi-finals last year, denying him the continental glory he craved with the Bundesliga champions.
Domestically, it was a different story for the Catalan, who bested Jurgen Klopp's Borussia Dortmund despite enduring a bloody nose or two at the hands of the Gegenpressing master.
Liverpool and Klopp ensured City ended 2016 with a 1-0 defeat at Anfield and a Guardiola wedded to methods under the microscope must guard against another reverse when their Merseyside rivals for Champions League qualification arrive at the Etihad Stadium on Sunday.
"Yes, it was a tough loss, but I wouldn't consider it a failure football-wise," said Sampaoli on Saturday when reflecting on the Leicester disappointment. There should be few surprises in store for Atletico and Simeone - or Klopp and Liverpool, for that matter.
"The influence of that game showed me again I am more convinced about what I want to do," said Guardiola, when reflecting on City's improved second-half showing in Monaco.
Like Sampaoli and Bielsa, he remains a fiercely protective keeper of the flame, willing to risk getting burnt in his latest high-stakes showdown.