Nicolas Jackson received a red card as Chelsea suffered a 3-1 defeat against Flamengo at the Club World Cup.
Pedro Neto put the Blues in front early in the game, but Enzo Maresca’s team collapsed in the second half in Philadelphia.
Chelsea let in two goals and had Jackson sent off for a dangerous tackle in just six minutes after halftime.
Their troubles increased when Wallace Yan sealed the victory late in the match, following earlier goals from substitute Bruno Henrique and veteran Danilo.
The final score, witnessed by a crowd of 54,019 at Lincoln Financial Field, left Chelsea with one win and one loss in Group D, despite initially appearing to be on track for the last 16.
It was a disappointing first full appearance for new striker Liam Delap, who was brought in to replace Jackson, but a significant win for Flamengo manager Filipe Luis, a former player at the London club.
The game started energetically and aggressively, and although the Brazilians seemed more comfortable in the 27C heat at kick-off, they struggled to create clear chances.
Former Chelsea player Jorginho had an early attempt which went over the bar, but goalkeeper Robert Sanchez was untroubled.
Despite limited possession and a quiet performance from Cole Palmer on the wing, Chelsea posed a threat on the counter.
Delap came close to scoring when he broke free and forced Agustin Rossi to tip the ball over the bar.
Chelsea took the lead when Neto capitalized on a fortunate deflection off Wesley's attempted clearance.
The Portuguese forward broke away from halfway and calmly scored his second goal of the tournament from outside the box.
Neto almost set up another goal for Delap, but his pass was intercepted by Wesley and Chelsea's penalty appeal was turned down after Enzo Fernandez went down in the box.
Levi Colwill cleared a Flamengo free-kick off the line, but it was in the second half that the Brazilians began to pose real threats.
Gerson missed a chance to equalize when his shot was blocked by Trevoh Chalobah after cutting inside Colwill. The ball fell to Gonzalo Plata, who somehow missed the target.
Chelsea came close to scoring a second goal when Leo Pereira, under pressure from Delap, directed the ball just wide of his own goal, but Chelsea struggled to control the game.
They were fortunate when Sanchez saved a shot from Plata over the bar.
The equalizer arrived just after the hour mark when Plata headed the ball back across goal and Henrique scored at the far post.
Chelsea were left reeling and were hit again moments later as Henrique assisted Danilo for a volleyed goal from a corner.
Chelsea's collapse continued as Jackson, shortly after entering the field, was shown a red card for a reckless challenge that caught Ayrton Lucas on the shin with significant force.
Yan deepened Chelsea's misery by scoring seven minutes before the end, adjusting his position and slotting the ball home after getting in the way of Plata's shot.