A loss came out of the blue for Frank Lampard's Chelsea who seemed in control of the game but created little going forward. It means that Chelsea are yet to taste victory at home under the new boss, although, the home fans will feel that they should've taken at least a point from the game as Ross Barkley hit the crossbar from the penalty spot in the 82nd minute.
Losing Mason Mount early in the game to an injury after he was on the wrong end of a horror tackle from Francis Coquelin, was a massive blow for this Chelsea team who struggled to find a creative outlet without him. It could also change the complexion of their tie against Liverpool this weekend.
The visitors will be overjoyed with the result as Albert Celades opens his Champions League campaign with Valencia with a win. There were plenty of murmurs of unrest within the Valencia camp after the controversial exit fo Marcelino, but now they can look forward to building on these early three points.
Plenty went wrong for Chelsea and right for Valencia, let's take a look at the hits and flops.
Flop: Ross Barkley
Substitutes taking penalties has been, in general, a fairly disastrous decision for many teams. Chelsea were the latest victim of this as Fikayo Tomori's header struck Daniel Wass on an outstretched arm, and although it wasn't caught in play, Cuneyt Cakir deferred to a VAR decision and awarded the spot-kick.
Ross Barkley, who had barely been on the pitch for minutes, stepped up to take it. A short discussion during which he dismissed both Jorginho and Willian, Barkley stepped up and found that his penalty kissed the top of the bar on its way out.
Had it been a good performance from Barkley other than the penalty miss itself, perhaps he would be spared the blushes. But he did little more than cycle the ball around, and created one dangerous situation but failed to find a team-mate after getting into the box.