Speaking to Voetball International about the crisis at Barcelona, Ronald Koeman said: "Messi has disguised everything. Now that he's gone, we are suffering.
"He was so good and he won. Of course he had good players around him, but he made the difference. Everyone seems better than they are because of him.
"This is not a criticism, but an observation. He delivered 50 goals last year: 30 goals, 20 assists. That's how big he was. He was an example for the players."
Barcelona have failed to hit the ground running following Messi's departure to Paris Saint-Germain, winning just two of their five opening games.
Koeman is reportedly a dead man walking at Camp Nou, with club president Joan Laporta already looking at potential candidates to replace the Dutchman.
