Chelsea lost 1-0 to Croatian side Dinamo Zagreb in their opening UEFA Champions League fixture on Tuesday.
Mislav Orsiic scored the winning goal for the hosts in 13 minutes.
Orsic ran from his own half, latching onto a ball from strike partner Bruno Petkovic, to outpace £70m signing Wesley Fofana before dinking the ball over Kepa Arrizabalaga.
Chelsea had a goal ruled out for offside four minutes after the break.
Ben Chilwell was offside when he set up Pierre- Emerick Aubameyang.
The Blues will host Red Bull Salzburg at Stamford Bridge in their next Champions League clash.
Source: Complete sports