Chelsea lost N'Golo Kante and Callum Hudson-Odoi to injury as they missed an opportunity to go third in the Premier League in an entertaining 2-2 draw against Burnley at Stamford Bridge.
Chelsea was hoping to bounce back from a 2-0 defeat to Liverpool in its previous top-flight outing but it dropped points once again and could be facing key games against Manchester United and Eintracht Frankfurt without Kante.
Burnley – yet to confirm its survival – went ahead through Jeff Hendrick early on, and although Kante and Gonzalo Higuain saw Chelsea turn things around in the space of two minutes, Ashley Barnes pegged it back in an enthralling first half.
Chelsea did much of the attacking after the interval but Sarri – who was removed from the sidelines in stoppage time – saw his side fail to make the most of top-four rivals Tottenham, Arsenal and United losing at the weekend.
Burnley edged ahead just eight minutes into a thrilling first half when Hendrick sent a fine volley into the bottom-right corner, but the Blues swiftly equalised thanks to Kante's left-footed effort into the roof of the net after fine work from Eden Hazard.
A brilliant move in the 14th minute saw Higuain score for the first time since 3 March, rifling in off the crossbar from a tight angle following Cesar Azpilicueta's clever flick.
However, Burnley restored parity 10 minutes later when Barnes latched on to Chris Wood's glancing header.
Having lost Hudson-Odoi late in the first half to an apparent shin problem, Kante was unable to come out for the second period due to a reported back injury.
Chelsea still looked cohesive going forward and nearly retook the lead in the 51st minute, but Tom Heaton thwarted Higuain – who reacted furiously when he was replaced by Olivier Giroud in the 77th minute.
The host piled the pressure on towards the end but failed to craft any further opportunities and Sarri's late ejection for dissent and a fracas after the final whistle – which was met with boos – summed up Chelsea's day.