"Guardiola told me here in England that it is very hard, the level is very high", he said.
It seems it's not just Sarri breathing new life into this Chelsea team.
Maurizio Sarri has given Chelsea fans an insight into what we could be looking for in the transfer market between now and the end of the week.
However, supporter RomaFC was left "very disappointed" by the Chelsea management's decision to offer an extension to Pedro, stating there are better youngsters already at the club.
He said: "We'd love to have him back".More news: A California Wildfire Whirled Into a 'Fire Tornado'
According to some reports, an expired passport is the reason behind Willian's absence, but Sarri has branded the situation as unusual. "I want to hear Courtois".
"We have very good midfielders, but maybe a midfielder with different characteristics [would be a good fit]".
Chelsea have signed former England No.1 Robert Green as backup this summer while Polish teenager Marcin Bulka has impressed during pre-season. Toby is a great boy and an excellent footballer, and I think he's one of those boys that whoever he plays for, he will be focused and will give everything he's got.