The Spaniard took a knock to his leg near his knee and is expected to resume training with the squad next week.

"Fabregas is out for this match. I hope he'll be able to feature next week. I'm not sure," Sarri told reporters.

"It's nothing serious but he has a very unusual injury. He has pain near the knee, not in the knee."

Sarri also said he was confident midfielder Eden Hazard would stay at the club this season. British and Spanish media reports have linked the Belgium international with a switch to Real Madrid, following in the footsteps of Thibaut Courtois.

The move could still go through as the transfer window for European leagues is open until Aug. 31. However, Sarri assured Chelsea supporters his talisman would stay.

"I've spoken with him often in the last 10 days but he has never said to me anything about this so I am sure Eden will be with us for this season," Sarri said.

Ahead of the clash at Stamford Bridge, the Italian backed his counterpart Unai Emery to make Arsenal a force to be reckoned with. The Spaniard suffered a 2-0 defeat by Manchester City in his first Premier League match since succeeding Arsene Wenger.

"Emery is a good coach," Sarri added.

"He won the Europa League three times, he won in France with Paris St Germain. Arsenal will be competitive. They will be able to fight for a place in the Champions League."