The reigning FA Cup winners triumphed thanks to Pedro's fifth minute goal and dominated for the first hour of the game, with only a series of Liam Reddy saves preventing them from extending their lead.

Chelsea also hit the post twice while Reddy may have got a finger on a curling shot from Cesc Fabregas early in the second half.

Glory pressed hard in the final half hour and almost levelled when Brendon Santalab headed wide, while Chris Harold and Fabio Ferreira created some dangerous half-chances.

"I think the result is not the mirror of the game," Sarri said.

"But it's more important in this moment. I'm satisfied about the first half, and the first 15 minutes of the second half, not for the last 30 minutes.

"I think Perth Glory has done a good match to defend in their city."

Sarri has only had a week in the job but the 2018-19 Premier League season is less than three weeks away.

Chelsea open their campaign at home to Aaron Mooy's Huddersfield and Sarri admitted they needed to improve.

"in the second half we have lost the distance between defenders and the midfielders," he said.

"But we knew that we have to work, we have to go back and work very hard.

"We know we have to improve very quickly."

The Italian was also asked about the futures of star trio Eden Hazard, Thibaut Courtois and Willian.

"I'd like to talk to a person face by face," he said. "I don't like to talk to a person by telephone.

"It depends on the club. It's clear that for me it's a pleasure to have Courtois, to have Willian, to have Hazard.

"But it doesn't depend on only on me. So we have to wait. I am confident."

Chelsea's pre-season heads to Europe next with the International Champions Cup where they'll face Internazionale in Nice on Sunday morning (AEST).