Defender Cesar Azpilicueta also offered his views to the club's official website, explaining that despite some early misfortune, he "trusts" his team-mates to deliver under the new boss.
Courtois reportedly told Sarri to his face on Monday that he wants to leave, with Real the preferred destination. The Spaniard appears to be highly regarded by his new manager - while he was criticised for miss passes last season, he is a hard worker and a leader within the team.
Newcastle are lining up swoop for Salomon Rondon and Danny Ings
Newcastle begin their league campaign by hosting Tottenham at St James' Park on August 11. The club announced that Muto has signed an initial four-year contract at St James' Park.
Premier League clubs have a shorter period to do their business than their European rivals, after choosing to slash their own transfer window. Everybody loves them [Courtois and Hazard] and I hope they can stay.
"I hope we can understand it quickly and can fight for all the titles", Luiz added. "We can all see their ability and what a great manager they have, but we are Chelsea and we have to believe".
"I'm not going to comment on all of that at the moment, it's a delicate matter", Courtois said.
Aguero ruins Sarri's Chelsea bow as Manchester City win Community Shield
There is certainly plenty of work for the 2016/17 champions to do if they are to close the obvious gap to their successors. It was also a landmark day for Aguero , who became the first player to score 200 goals for Manchester City .
It has left Chelsea's options limited and not obvious if they are to sell Courtois to Real Madrid.
Another player still being linked with a Chelsea exit is Brazil winger Willian.
The 59-year-old Italian's style has been likened to Pep Guardiola's.
However, with Conte now gone and replaced by Maurizio Sarri, Willian is looking ahead to a sixth season as a Chelsea player.
Venezuela's Foreign Minister: Probe Into Attack Against maduro Points to US, Colombia
Arreaza thanked the solidarity shown by various governments and organizations in rejection of the attack against the president. The drones did not reach him, officials said, but it was not clear if they were shot down or exploded prematurely.