The young midfielder has warned his teammates against thinking their place in the semifinals of the Champions League is already sealed.
Ezequiel Lavezzi's early opener was cancelled out with halftime looming by an Eden Hazard penalty, but David Luiz inadvertently tapped the ball into the back of his own net before Javier Pastore finished the Blues off in stoppage time.
The midfielder, who was brought off with an unspecified but seemingly minor injury late in the game by Laurent Blanc, has called for PSG to resist complacency.
"We will not commit the mistake of thinking we are already in the semi-finals," he told Sky Sport. "There are still 90 minutes left in the tie and we will try to attack in the second leg."
Verratti has been regularly linked with a return to Serie A since his move to Parc des Princes, but the 21-year-old has looked to end rumours by categorically stating he wants to stay in Ligue 1.
"I have no nostalgia for Italy," the Azzurri international added. "I enjoy this experience and I hope to stay in Paris for as long as possible."
The Parisiens will go to Stamford Bridge next Tuesday looking for a spot in the last four of the Champions League.