What happened to Bielsa's Athletic Bilbao side that humbled Fergie and co?

Bielsa, much like Manchester United boss Ralf Rangnick, arrived in England on reputation, but results were soon demanded.

A foreigner who came with mystique and totally legitimate tales of disciples such as Pep Guardiola and Mauricio Pochettino - as well as revolutionary tactics - Bielsa is now a household name in Britain.

The question about a lack of trophies hung over the Leeds boss when he arrived in Yorkshire in 2018, but in 2020 he lifted the EFL Championship trophy and created history at Elland Road.

Returning the Whites to the Premier League for the first time in 16 years, Bielsa followed it up with a highly-entertaining ninth-placed finish, seemingly ending any questions about his pedigree and standing in the game.

Doubts have seeped back in with Leeds' horrendous injury-hit season this time round, but in reality they never should have existed in the first place, with Bielsa introduced to England almost a decade ago.

The enigmatic Argentine had been a background figure when his unique 3-3-3-1 formation employed with the Chilean national team peaked interest at the 2010 World Cup, but his next job was the difference maker.

Keen on international football and teams with identity, Bielsa took the second best thing in 2011 when he signed for Athletic Club, taking the helm of a side that only employs players native to the Basque region of Spain.

What followed was a two-year stint that still has Guardiola spellbound, calling Bielsa 'the best manager in the world' before he met his Barcelona side in the 2012 Copa del Rey final.

His Athletic side ultimately fell short in both the Spanish cup and the Europa League final in one incredible season, but the journey to both inspired thousands, particularly when it went through Manchester.

Sir Alex Ferguson's United have rarely been so comprehensively out-worked than their 2012 last 16 meetings with Bielsa's side, dominated on and off the ball with a 5-3 aggregate win for the Spanish side.

Bielsa later revealed that Ferguson told him he wasn't surprised his team were beaten or out-worked but, "What did surprise him was on the day of the game, in the morning, my team had trained for an hour-and-a-half," Bielsa said.

He was able to keep his side together for one more season, but the following summer saw key the departures of Javi Martinez and Fernando Llorente who scored goals in both legs.

Martinez will go down as the most decorated Spaniard to have never played for Real Madrid or Barcelona, with two trebles picked up at Bayern Munich as well as World Cup and Euros titles.

Llorente was far more travelled than Martinez, winning trophies with Juventus, Sevilla and Napoli, as well as his European heroics with Tottenham.

The towering striker managed key goals throughout his career, including one that knocked Manchester City out of the 2019 Champions League quarter-finals in the most stunning fashion and later earned a spot in the final.

Ander Herrera followed the pair out of the door the following summer, joining previous opponents United and then PSG, picking up numerous titles along the way.

Their understated captain and right back on the against United, Andoni Iraola departed a year later, joining New York City where he was able to play alongside Frank Lampard and Andrea Pirlo.

Now he's coaching Madrid minnows Rayo Vallecano, and giving them a shot at Champions League football in their first season back in LaLiga.

Another Bielsa disciple has been born, and Atletico Madrid are reportedly already interested should the Diego Simeone era end early.

But the one player from those sensational games at Old Trafford and San Mames who stood out more than any other is still there, with Iker Munian now captaining the side.

The small but undoubtedly tricky wide man led his side to Spanish Super Cup glory last year, and almost did the same again this term with a stunning goal to knockout Barcelona in the semi-finals this year.

That win showed Athletic are back causing upsets, with an impressive squad of homegrown talent allowing Muniain to dream once again.

But when it comes to unforgettable moments, the 2011 vintage that left Ferguson humbled will surely never be beaten.

Bilbao's starting XI

G Iraizoz, J Aurtenetxe, F Amorebieta, Javi Martínez, A Iraola (c), Ó de Marcos, A Iturraspe, A Herrera, I Muniain, M Susaeta, F Llorente