Crystal Palace spoiled Jose Mourinho's 100th Premier League home game as Chelsea manager by defeating the reigning champions 2-1 at Stamford Bridge this afternoon.
The Blues had looked on course to win at least a point when Radamel Falcao cancelled out Bakary Sako's opener on 80 minutes to open his account for the West Londoners.
However, Joel Ward was on hand to head home the winner a minute later in a defeat that leaves that Mourinho's men eight points behind Manchester City already.
The champions, fresh from a first win of the season at West Bromwich Albion last week, toiled in the first quarter against a resolute Palace defence.
However, Pedro, who marked his debut with a goal at The Hawthorns, was very nearly on target again as he curled just wide of the post on 19 minutes.
At the other end, another summer signing in the form of Sako proved the Eagles' most promising outlet, as the winger cut inside Branislav Ivanovic before forcing Thibaut Courtois into a smart save.
On the day his 100th Premier League game at home, it became clear that the hosts would need to improve in order to help Mourinho mark his century in winning fashion as the visitors continued to hold their own.
However, they almost broke Palace's resistance in the closing stages of the half, as Alex McCarthy denied Pedro in a rebound moments after spilling Cesc Fabregas's effort.
Only one of Mourinho's first 99 league games at the Bridge had ended in defeat, but the Eagles threatened that solid record with a fast-and-furious start to the second period.
Sako continued to threaten and he set up Connor Wickham, whose first-time shot was kept out by Courtois, before the ex-Wolverhampton Wanderers man then found himself denied by the Belgian stopper as Palace dominated.
Gary Cahill saw his header cleared off the line, before Alan Pardew's side opened the scoring moments later when Sako rifled past Courtois at the third time of asking.
From there, Pardew's men continued to pile forward in search of a killer second, with Yannick Bolasie - back in the squad following the death of his father last week - came close on two occasions.
Against the run of play, however, Falcao climbed off the bench to steer a header beyond the reach of McCarthy, but parity only lasted for a moment as Ward re-established the lead with a firm header on 81 minutes.
Falcao then turned Ivanovic's rifled shot just wide in the closing stages as the Portuguese manager suffered his second home Premier League defeat.