Battling Salzburg held a disjointed Chelsea to a 1-1 draw in the Champions League on Wednesday, severely denting the 2021 winners' chances of qualifying from Group E.
A tireless Raheem Sterling put the London side ahead in the 48th minute, latching on to a low cross from Mason Mount and shooting beyond the diving Philipp Kohn into the left corner of his net.
It was his first Champions League goal in Chelsea colours and the first goal under new coach Graham Potter, who took over last week following the shock dismissal of Thomas Tuchel.
But the well-organised Salzburg side, who also drew with AC Milan last week, never stopped running and were rewarded in the 75th minute when Noah Okafor sent a low cross home after Cesar Azpilicueta and Thiago Silva had failed to clear the ball.
Former Brighton & Hove Albion boss Potter said he was disappointed with the result "but the boys gave everything. It's impossible to control the game for 90 minutes and the period we didn't do so well they scored.
"It's always irritating when you concede but the overall defensive performance was good. Little details you have to improve. Not the result we wanted but we will take the point."
Chelsea held Salzburg in their own half for long periods but failed to find the telling final pass. New signing Pierre-Emerick Aubameyang could not get on the end of a series of crosses and Kai Havertz often looked isolated.
Sterling, playing on the wing out of his normal position, told BT Sport: "I think with how we played, the chances we created, we dominated.
"It's a bad result in the end but we played some good football at times. I took the chance but we have to finish the job off. It felt like we were in control, but one chance one goal for them. Under a new manager we will get better and keep progressing."
Chelsea lost their first group game to Dinamo Zagreb last week and Tuchel was sacked the following day. On Wednesday, the crowd chanted Tuchel's name and applauded at the 21st minute of the match in recognition of the 2021 title when Chelsea beat Manchester City in the final in Porto.
Chelsea, who followed that triumph with victory in the World Club Cup earlier this year and were favourites to qualify from Group E, now languish at the bottom of the group with one point.