Marco Verratti says Paris St Germain have learned lessons from their shock defeat at Rennes.
PSG won their first 14 matches last season on the way to a sixth domestic title in seven years.
But the champions lost their second game of the new Ligue 1 campaign last weekend as Rennes recovered from a 1-0 deficit to win 2-1.
"It's those sorts of games that make us understand that we have to have the same level of intensity throughout a whole game," Verratti said at a press conference ahead of Sunday's visit from Toulouse.
"We had a good pre-season. We're still not 100 per cent, which is normal after just two league games.
"But we feel good. That's the most important thing.
"The defeat to Rennes? We don't like losing. We have often had tough times there, but it's the start of the season and we're still not in top form."
Italy midfielder Verratti is now in his eighth season at the Parc des Princes, having joined from Pescara in 2012.
The 26-year-old has made over 260 appearances for PSG and says he relishes the responsibilities that come with being a senior player.
"I've had them ever since I arrived," he said. "I was young, but it's normal to have responsibilities when you play for a club like Paris St Germain.
"I feel important for the team and I want to help it even more.
"Last season, all my problems were linked to my groin problem.
"I couldn't take a long enough break to deal with it fully, but now I feel really good. That's very important."
Neymar (ankle) is expected to be missing again for PSG, along with Thilo Kehrer (foot), Ander Herrera (calf) and Presnel Kimpembe (groin).
But Senegal midfielder Idrissa Gueye, who made a reported £30million summer move from Everton, could make his debut having travelled with his team-mates to Rennes.
Gueye's inclusion could see Marquinhos drop back into defence, with Thiago Silva or Thomas Meunier rested.
Toulouse have a point more than PSG having drawn at Brest and beaten Dijon.
"There was some interesting things but we still have to work hard," Toulouse head coach Alain Casanova said after the 1-0 win over Dijon.
"We were too wait-and-see. It's also my fault.
"In the second half we never let our level drop, we absolutely wanted all three points, and on the whole, I think the win was deserved."
Injured pair Corentin Jean and Agustin Rogel remain out, but Nicolas Isimat-Mirin could make his debut after joining on loan from Besiktas.
Jean-Victor Makengo, the match-winner against Dijon, is expected to be fit despite coming off with a knock late in that game.