Chelsea lost their opening Champions League fixture for the first time in their history as they were condemned to a 1-0 defeat by Valencia.
Rodrigo's second-half goal was enough to secure all three points at Stamford Bridge, as Ross Barkley missed a penalty with two minutes to go.
Outside of the spot kick, the Blues failed to create many clear-cut chances, with the attack which seemed so free-flowing against Wolves being mostly shutdown by a resolute Valencia defence.
Here are the main talking points:
Missing Mount a real worry
One of the stars of the season in West London has been Mason Mount.
The 20-year-old has relished every opportunity Frank Lampard has given him, and already looked at home in the Champions League nine minutes into his debut.
Following a shocking challenge from Francis Coquelin, Mount hit the deck, and he was forced off just 16 minutes into the game.
Pedro came on to replace the England international and put in a poor performance, as he failed to replicate the attacking prowess the young side had shown in recent weeks.
It is yet to be known whether Mount will be fit for the visit of Liverpool this weekend, but real problems lie for Chelsea if he is not.
His role so far this season seems irreplaceable at this time, and his work-rate and ability on the ball is crucial to defeat the Liverpool press.
Worrying times for Chelsea.
Reece James suits this team perfectly
One of the most notable aspects of how Chelsea attacked last night and in a few games this season has been the use of Cesar Azpilicueta down the right-hand-side.
With three centre-backs in play now too, he has had even more opportunity to attack, however his end product has been a massive let down for the Blues.
Enter, Reece James.
Wigan Athletic's player of the year has 45 minutes under his belt for the Chelsea development squad, and if his play last season is anything to go by, the 19-year-old is tailor made for the position at Chelsea.
His delivery from a number of angles looks extremely impressive, and he has shown the ability to strike from range.
Chelsea need him fit, and soon.
Is it time to worry about our Kepa?
Chelsea are yet to keep a clean sheet in all competitions this season, and while Kepa Arrizabalaga has secured the number one shirt for Spain, he has the lowest shot to save ratio in the Premier League.
Obviously, clean sheets can not be blamed solely on a goalkeeper, as Frank Lampard has tried a number of players and systems whilst being without his number one centre-back in Antonio Rudiger.
However, the £71 million pound man is struggling to show his worth right now, again being beaten by a shot he'll feel he should've kept out against Valencia.
Last season, the former Atletico Bilbao man produced a number of stunning saves, but showed moments of controversy, highlighted by his antics deep into extra time of the Carabao Cup final.
It might be unfair the judge until things get sorted out at the back, but it's been far from impressive from the Spaniard so far.