The Giallorossi were crushed 4-1 by Juventus and already 3-0 down within the opening 19 minutes.
Sabatini said: "Many people said Roma would be challenging the top clubs for the title, which up until tonight was fairly plausible. The Coach tries to give the team a certain approach, but they lack temperament on the field at times.
"We are asking ourselves questions with honesty. I say that more or less all the decisions were made with the Coach, so if there were mistakes in buying players then it was collective."