Nottingham Forest on Saturday stunned Chelsea 1-0 at Stamford Bridge as Anthony Elanga came off the bench to score the game’s only goal.
Forest rode on their mid-week Carabao Cup win to make it back-to-back after Elanga’s early second-half strike secured a 1-0 victory away from home.
On the other hand, the Blues stuck with the same side that had outclassed Luton last weekend but gifted the visitors all three points.
The visitors, who had already performed admirably in narrow defeats at Arsenal and Manchester United, finally got a result against a top-six club that their displays had deserved.
Despite nine new signings, Mauricio Pochettino has made just two changes to his starting line-up in their four Premier League games this season.
Read also Nottingham Forest look to cause an upset at Stamford Bridge
It was club-record signing Moises Caicedo who was at fault for Elanga’s goal, while new signing Cole Palmer could not stamp his mark on proceedings as he made his debut off the bench.
Raheem Sterling, fresh off his brace against Luton, had a good chance in the opening moments, but Ola Aina’s brave challenge kept the Chelsea man at bay.
As Sterling set about trying to prove he was worthy of a place in the England squad he was once again omitted from last week, it was Conor Gallagher – who did make Gareth Southgate’s cut – who bent a shot just wide of the target.
Sterling, the liveliest spark in Chelsea’s attack during a forgettable first half, crossed for Ben Chilwell but could not turn it home.
Forest enjoyed some possession down their right and earned a free-kick in a dangerous area when Thiago Silva dragged Taiwo Awoniyi to the ground, with the in-form striker flashing a shot over the crossbar after the resulting set-piece dropped to him in the box.
Having already scored at the Emirates Stadium and Old Trafford this season, Awoniyi came close again with an acrobatic close-range effort that flashed just wide of a post.
Read also Arsenal vs Nottm Forest: Taiwo Awoniyi scores in loss to Gunners
The visitors were forced into a change in first-half stoppage time as Danilo limped off after chasing a ball over the top, with Elanga on in his place.
The Sweden forward signed from Manchester United for a reported £ 15 million got off the mark for Forest shortly after the restart.
A heavy touch in midfield from Caicedo gifted possession to Forest with Chelsea’s defence out of position, and the away side took full advantage.
Awoniyi threaded a pass through the legs of Thiago Silva and into the path of Elanga, who coolly slotted past Robert Sanchez to break the deadlock.
Chelsea toiled in their quest to draw level as Pochettino threw on Noni Madueke, Palmer, Ian Maatsen and Mykhailo Mudryk in search of a goal.
It should have come through Nicolas Jackson, but the summer arrival from Villarreal turned over on the stretch from six yards after some good work from Sterling picked him out in a great position.
