It's not hard to imagine Sarri's high defensive line being torn to shreds, particularly if Rudiger's injury deprives the Blues of all recovery speed.
"In Italy if you are playing in the Champions League you can ask to play the match before on a Friday or Saturday", the former Napoli boss said. Then we have played well in the second half, and very well in the last 25 minutes.
'We are improving in the defensive phase. City could not live with them three times out of four meetings last season, and Chelsea at this stage are simply City-lite in style and quality.
For Sarri, more time is needed.
'We have started to work together 40 days ago, less 10 days for the worldwide break, so for us it is a bit early.
Hazard told Sarri after returning from the September global break with Belgium and his hat-trick in the 4-1 win over Cardiff that he was exhausted.
Chelsea drop first points of season in draw at West Ham
'We need to move the ball quicker, ' said Sarri.
Pedro was Chelsea's only significant absentee, thanks to the shoulder injury he picked up in the final seconds of the midweek win over PAOK, but he was missed.
That tactic nearly paid off in the 29th minute when Felipe Anderson broke down the left before playing in Michail Antonio but the attacker - in the team as a replacement for the injured Marko Arnautovic - blazed a shot high over the crossbar after getting in behind the Chelsea defence.
First, after being put through on goal by Felipe Anderson, he could only fire over when one-on-one with the 'keeper.
While the world's most expensive goalkeeper deserved credit for a fine save, Arnautovic, who has scored three and assisted another of West Ham's five goals this season, would likely have converted one, or both, of Antonio's chances.
As the interval approached Hazard fed Willian who touched the ball back across goal for N'Golo Kante, but the Frenchman glanced his header the wrong side of the far post.
But for the most part the visitors were crowded out by a determined Hammers opposition, with Fabian Balbuena doing particularly well to nullify the unsafe Hazard.
Several killed in attack on Iranian military parade
Semi-official news agency Mehr said further shooting broke out as some of the attackers who managed to escape were being chased. ISNA quoted Khuzestan province's deputy governor Ali-Hossein Hosseinzadeh as saying: "One of the martyrs is a journalist".