Arsenal missed a string of great chances - Pierre-Emerick Aubameyang shot over from close range with the goal at his mercy - but was level at halftime after goals by Henrikh Mkhitaryan and Alex Iwobi in a five-minute span.
Despite making 25 appearances for the Eagles last term and Chelsea making it clear they want to keep their man, it remains to be seen how much first-team football Sarri will give him.
Chelsea secured the Real Madrid midfielder Mateo Kovacic on loan with no option to buy this month, with the Croatia global effectively taking Loftus-Cheek's place on the bench against Arsenal, and have preferred Ross Barkley in midfield for the team's first two Premier League games.
"I think the result is 3-2, but we also think we did chances to do more score".
"Three points is an important target for us, we did very well for 75 minutes but inside that, 15 minutes were terrible", he stated.
"The attacking moment is all the team and the defensive moment is all the team".
"In the second half we played with two midfielders, 19 and 21 years old".
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Turkish President Tayyip Erdogan meets with Emir of Qatar Sheikh Tamim bin Hamad al-Thani in Ankara, Turkey August 15, 2018. Erdogan has warned Turkey could seek alternative partners, pointing to Ankara's strong ties with Russia, Iran and China.
The win makes it two defeats out of two for Emery, with the Arsenal defence needing major work, while Granit Xhaka continues to labour in midfield.
Sarri admitted his side suffered a "horrible" 15 minutes which could have cost them dear.
Morata's fourth goal in 2018 was another positive for Chelsea, but Sarri believes there is more to come from the Spain worldwide. I think that the players were very good in the second half.
"There was never a thought for me to leave", the striker said.
"It is better to be on the pitch than on the bench, but the boys when they are playing did well, so if I'm on the pitch for 15 or 20 minutes, I do my best", he told BT Sport. "So today I am just happy for the win".
However, Chelsea want Loftus-Cheek to stay and fight for his place despite the player being upset at being dropped from the squad.