Former Paris Saint-Germain player and backroom staff member Alain Roche has called Leonardo's decision to quit the French champions "catastrophic" and warned it could harm the club's summer transfer policy.
The club announced on Wednesday they had been informed by their Brazilian sporting director, 43, of his decision to leave his post come the end of the transfer window on September 2.
Having re-joined the club as part of their recruitment team in 2003, Roche who played alongside Leonardo at PSG, initially worked with his former team-mate following Qatar Sports Investments' (QSI) purchase of the club in summer 2011 before eventually being asked to leave in August 2012.
The former defender, who played at the Parc des Princes between 1992 and 1998, notably winning the 1995-96 Cup Winners' Cup, told RTL he was not surprised Leonardo had now joined him in heading for the PSG exit, but added the public announcement could not have come at a worse time.
He said: "I'm always a little wary of press releases having worked at the club. Is it really a resignation? Is it an agreement between the two parties because the club didn't want him? That's perhaps the case too.
"You can imagine anything and everything. But whether the decision came from Leonardo himself or whether it was from the club with his agreement, it's a catastrophic moment to do it.
"Imagine yourself in the shoes of a player who's contacted by PSG. It'd be normal he ask himself some questions. Ancelotti, one of the best coaches in the world, decides to leave, now the sporting director. What's going on at that club?"
Roche concluded: "It's complete instability. When you have Ancelotti who decides to leave even though he's at a club with an exceptional project, you have to ask yourself what's happening with the owners."
Despite the announcement of his imminent departure, French media reported Leonardo had met Edinson Cavani's agent at the Parc des Princes on Wednesday to finalise details of the Uruguayan's move from Napoli to the French capital where a five-year contract worth an annual €10 million reportedly awaits him.
Long-serving centre-back Zoumana Camara, 34, who signed a one-year contract extension last month, said Leonardo's absence would be felt even if PSG would continue to progress under new coach Laurent Blanc and its ambitious Qatari owners.
"The club's more important than anything. The officials and players are just passing through. It's a personal decision, and we respect it," the former Saint-Etienne defender told RMC.
"We thank him for everything he's done for PSG. The life of the club continues. Leonardo is very professional, very committed, very intelligent. He speaks several languages and gives a lot of himself to his work. He's very thorough in what he does. The fact he's leaving at the end of the transfer window proves his professionalism."