Marcelo Alberto Bielsa Caldera (American Spanish: [ma?'selo al'ße?to 'ßjelsa], nicknamed Loco Bielsa ['loko 'ßjelsa], meaning Madman Bielsa; born 21 July 1955) is an Argentine professional football manager and former player who played as a defender.
He is the head coach of Championship club Leeds United.
Bielsa has managed several football clubs and also the national teams of Argentina and Chile.
With Chile, he achieved cult status due to the improved results of the national team under his leadership.
His personality and gestures during his stint in Chile captured the attention of media and unleashed a series of minor controversies both in sports and politics.
He had a two year-spell in Spain at Athletic Bilbao between 2011 and 2013, leading them to domestic and continental cup finals in the first season, though losing both.
On 8 August 2015, Bielsa resigned as coach of Marseille after just over a year at the French club.
On 15 June 2018, he was appointed manager of Leeds United.