Reece James fitness issues are becoming a long-term concern for Chelsea
Chelsea suffered another dismal away defeat at Everton as they failed to toughen up at Goodison Park.
Mauricio Pochettino called on his players to show "fight" or "suffer" before kick-off - and they suffered.
Chelsea did their level best to compete but injuries to Reece James and Robert Sanchez, along with a lack of match fitness in striker Armando Broja and defender Benoit Badiashile, left the Blues short.
Externally, Mauricio Pochettino will more face questions after this 2-0 defeat.
Reece James keeps breaking down
The Chelsea captain lasted just 26 minutes before being substituted.
He played well within himself and had not been particularly stretched, but he could not get through even half of the game.
It follows just a 45-minute appearance away at Manchester United in midweek.
The question is whether Chelsea can rely on James's long-term fitness again without surgical intervention.
He has missed more matches than he has played this season.
Mudryk blows hot and cold as the goals dry up
Mykhailo Mudryk was Chelsea's main threat as they misfired on Merseyside.
The Ukraine international ran a 38-year-old Ashley Young ragged in the first half, so much so that he Everton man had to be taken off.
Nathan Ferguson gave a better go of stopping Mudryk, but the blisteringly quick winger still got past him multiple times.
Unfortunately, he could not find the final pass or get good enough shots away to get his team a goal.
But he deserves credit for being more dangerous than most of his team-mates, with all of Raheem Sterling, Cole Palmer, Armando Broja and Nicolas Jackson failing to strike.
Palmer was the best of the rest and Jackson missed the best chances of the game after being introduced from the bench.
Robert Sanchez also injured
Goalkeeper Djordje Petrovic came on for his Chelsea debut in the second half.
Sanchez was hurt just before Everton's goal after flapping at a corner, needing treatment for a prolonged period but playing through the pain.
The injury could have slowed him down when rushing to close down Dominic Calvert-Lewin's one-on-one, with the ball rebounding to Doucoure for the crucial opening goal.
Petrovic flapped at a cross in his only action, allowing Lewis Dobbin to add to the score - a difficult introduction to Premier League football.
