Thomas Tuchel has revealed that Andreas Christensen was withdrawn at halftime with an injury during Chelsea's defeat to Arsenal at Stamford Bridge.
The Blues fell to a difficult loss to Mikel Arteta's side, who came into the game having lost their last three games on the bounce, thanks to a brace from Eddie Nketiah as well as goals from Emile Smith Rowe and Bukayo Saka.
And it was Christensen who handed the Gunners the early impetus, with a woeful backpass allowing Eddie Nketiah to steal in for his first of the game.
The defender, who struggled in the first half, was removed at half time, and Tuchel was quick to suggest that this came owing to an injury rather than as a result of his sub-par performance.
It was the same issue that saw him fail to come out to the bench for the second half, either, instead staying in the dressing room for treatment.
Chelsea see records tumble
In falling to the Gunners, Chelsea have set a pair of unwanted records.
They lost their third straight home game for the first time since 1993-94, while Arsenal's win also meant that the Blues have conceded four goals in back to back home league games for the first time since the 1989-90 season, before the Premier League's inception.
In many ways, the performance and result were somewhat expected. Chelsea are comfortable in third place in the Premier League, not endangering the runaway pair of Manchester City and Liverpool above them nor too much at risk of being dragged into a battle for European football, with a five-point cushion on the sides below them.