However, Chelsea recovered their grip on the game and the introduction of Eden Hazard gave Chelsea a much-needed boost.
The Belgium global was strongly linked with a switch to Real Madrid after hinting earlier this summer that he would be open to a move away.
And he is happy to accept staying in west London - for the time being at least.
"You know what I said after the World Cup".
"We have to improve in the defensive phase and I'm not talking about only the defenders".More news: Trump Lashes Out at Russia Probe as 'McCarthyism'
"He works with the ball always and when you always have the ball you have more chances and the strikers have more chances", Morata said of Sarri.
"I am really very happy", Sarri told ChelseaTV when asked about Kovacic. "I am going to stop for just one or two years then I will start again".
"Leave this year? I will not leave".
The Croatian worldwide arrived at Stamford Bridge on a season-long loan deal towards the end of the summer transfer window but was forced to wait until the second game of the season to make his debut for Chelsea. We lost the distances I think, we were not able to cover the last third, or press as a team, only one player to player. It would be a little odd if they (Chelsea) sell me now while they can't recruit a replacement. We could see [against Arsenal] that the fans like me a lot.
"I think that the players were very good in the second half".
Hazard has two years to run on the five-year contract he signed in February 2015.
Mateo Kovacic was content with how he performed on his Chelsea debut as the Blues narrowly defeated Arsenal 3-2.