Joan Laporta accused Barcelona president Josep Maria Bartomeu of 'cowardice and ineptitude' in the wake of their 8-2 Champions League humiliation by Bayern Munich.
Bartomeu apologised to the club's supporters after Barcelona's heaviest defeat since 1940 and pledged to make 'decisions' to get the club back on track.
This is likely to include the sacking of manager Quique Setien, who was only appointed back in January.
But that didn't spare him criticism from former Barcelona president Laporta, who said Bartomeu isn't fit to make such decisions.
Laporta tweeted: 'After this very painful defeat, the statements of President Bartomeu are, once again, a sign of cowardice and ineptitude.
'The incompetence of him and his board disqualifies them from making more decision that condition Barca's future.'
Laporta was Barcelona's president between 2003 and 2010 during which time they won four LaLiga titles, the Spanish Cup and the Champions League twice.
He was succeeded by Sandro Rosell, who served for four years before Bartomeu took the role in January 2014, initially as interim president.
Bartomeu's tenure has seen the club win three league titles, four Spanish Cups and one Champions League. He defeated Laporta in the 2015 presidential election.
But they have failed to win any silverware this season for the first time since 2007-08, losing out to Real Madrid in the LaLiga title race and losing to Athletic Bilbao in the Cup quarter-finals.
Their eight-goal humiliation at the hands of Bayern in the Champions League quarter-finals represents a fresh low.
Speaking after the Bundesliga champions' demolition of his side, Bartomeu insisted some of the tough decisions have already been made.
'It's a really heavy defeat,' Bartomeu said. 'I want to congratulate Bayern, who played a great game. They deserve to go through to the semi finals. We weren't at our best, nor near it.
'Today was a disaster and now we have to make decisions. We've already thought about some of them.
'Today isn't a day for decisions. We want to apologise to the fans, members and Barcelonistas.'
However, when pushed on who and what those decisions would involve, Bartomeu - who will now be under severe pressure from rival candidate Victor Font ahead of elections next year - did not reveal the club's intentions.
'I'm not going to say what [decisions] they are because some of them have already been made and others will be made,' he added.
'Today is a day to reflect. From tomorrow, we'll try to lift the spirits of all the Barcelona fans and we'll make decisions from next week.'