But after his successful return to F1 following a one-race ban, rookie Frenchman Grosjean also praised his Australian rival.
"Webber was not very fair as he completely cut the first corner," he is quoted by RMC Sport.
"But I have to say that at Monza he was the first to come and see me to say it (the ban) was a little harsh. I get on well with him," added Grosjean.
The Lotus driver revealed that he has made some tweaks to his race preparation, so that he is now "better" prepared for the start of the races.
"There are six races left and I want to go on the podium," said Grosjean.