Jorge Sampaoli was hired as the new coach at Marseille with Pablo Longoria replacing Jacques-Henri Eyraud as club president amid sweeping changes on Friday.
The upheavals were announced in a statement on the club website and could help appease a tense climate with the fans.
Eyraud was under increasing pressure to leave and unpopular with supporters, who stormed the club's training complex last month and caused widespread damage, tagging walls there and around the city with insults in a bid to push him out.
Former Argentina boss Sampaoli replaced Andre Villas-Boas after he resigned this month. Villas-Boas was angry after not being consulted over moves in the January transfer window. Sampaoli steps in for interim coach Nasser Larguet, who took charge for a handful of games after Villas-Boas walked away.
The 34-year-old Longoria initially joined Marseille in a sporting director's role last August. Marseille's American owner, Frank McCourt, who is set to meet with disgruntled supporters groups, said the time was right for change.
"It's a new chapter for Marseille and I personally commit myself to making sure it's a true success,'' he said in a club statement. "I've trusted Pablo with the presidency ... His main priority is to bring soccer back to the heart of Marseille.''
The high-octane Sampaoli coached Argentina during an ill-fated World Cup campaign in 2018, when he often stood out for his touchline rants. The 60-year-old Argentine previously coached Chile -- winning the 2015 Copa America by beating Argentina in the final -- Spanish club Sevilla FC, and Brazilian side Atletico Mineiro, where he stayed less than one year. Marseille have contracted him to June 2023.
"Marseille is a people's club and I myself can feel this warmth,'' Sampaoli said. "In the world there are calm and intense places. It's the latter that I want and I accepted without hesitation. This club has a soul."
Marseille have won a record-tying 10 league titles -- the last in 2010 -- and is the only French club to win the Champions League, in 1993. But this season has gone poorly, with Marseille knocked out of the Champions League group stage in last place.
Marseille are seventh in the French league and way off the European places ahead of Sunday's home game against second-placed Lyon.