The Brazil playmaker left Milan on Monday, prompting protests from Rossoneri fans, while Inter striker Zlatan Ibrahimovic is hoping to join Barcelona.
The loss of possibly the two best players in Italy would be a huge blow for the struggling league, which has slipped well behind Spain and England in terms of appeal and financial clout.
Now Pirlo, who has been linked in the media with former Milan boss Carlo Ancelotti at Chelsea, has expressed doubts.
"We have taken Kaka's exit badly," he told reporters with the Italy team at the Confederations Cup in South Africa.
"We'll see if I leave. For now, no, but looking ahead we will see."
Maicon, among Serie A's best players, is even more unhappy.
"For three years Inter have treated me with indifference, maybe because they are worried about keeping Ibrahimovic happy," the Brazilian told Wednesday's Gazzetta dello Sport. "I'm searching for joy, at Inter or another club."
Milan striker Alexandre Pato has said he is considering his future but club bosses have said there would be no more big departures with the focus shifting to a replacement for Kaka.
Chief executive Adriano Galliani has said Wolfsburg's Edin Dzeko is a target and the Bosnian seems keen to move from the German champions.
"It is still not done but I hope so. The Rossoneri, along with Real Madrid, are the essence of soccer," he told reporters.
