If Thomas Tuchel wasn't concerned before, Tuesday night's performance will provide plenty of reasons to worry as the Blues continued a lacklustre start to the Premier League season.
Chelsea were deservedly beaten 2-1 by Southampton as goals from Romeo Lavia and Adam Armstrong cancelled out an opener from Raheem Sterling. The loss is Chelsea's second in three games, having previously been blasted 3-0 by Leeds before a narrow 2-1 win against Leicester.
The Blues looked a step off the pace, with Southampton trampling an overrun Chelsea midfield trio. The absences of Reece James, N'Golo Kante and any sort of No. 9 were felt on a night to forget for Tuchel and his players.
With the loss, Chelsea now have just seven points through five games and are in danger of falling out of the title race.