Liam Rosenior watched on as his new Chelsea side fell to a 2-1 defeat at local rivals Fulham, following a first-half red card for Marc Cucurella.
Liam Delap had given the visitors hope of salvaging a point with his first Premier League goal for Chelsea after Raul Jimenez's excellent header, but the in-form Harry Wilson found the bottom corner with the help of a deflection to grab Fulham the win and bragging rights over their neighbours.
Rosenior, who was sat in the stands at Craven Cottage, will now take over a team which has just one win in their past nine Premier League games.
He will have seen first-hand how ill-discipline continues to hold Chelsea back. Cucurella's sending off for hauling down Wilson just 22 minutes in was the team's seventh red of the season in all competitions. This was the third time they've lost a league game after going down to 10. A flurry of yellow cards after Cucurella's red followed.
Rosenior will also have heard the disgruntlement of the club's supporters, who throughout the match chanted against Chelsea's hierarchy and sung for former owner Roman Abramovich.
Caretaker Calum McFarlane was unable to build on the last-gasp draw at Man City in his previous game in charge and hands over Chelsea eighth in the table. He will rue the red card, given Andrey Santos had hit the bar from a corner before Cucurella's foul - but the Spanish defender could have no complaints about the decision.
Wilson thought he had capitalised on Fulham's numerical advantage just before the break but saw a strike ruled out by VAR for an offside from Jimenez earlier in the move. But the Mexcian made up for it with a brilliant header on 55 minutes and when Wilson finally got in on the act, Craven Cottage erupted.
Fulham's win - inspired by the red-hot Wilson, who has nine goal involvements in his past 10 games - lifts them into the top half of the table.
Fulham boss Marco Silva:
"[Wilson] has been incredible. Right now everything that he touches becomes something magic. The fans should enjoy and try to take the best from him.
"Now it's easy to talk but Harry is going to remember last season, we were having some conversations, that he was not in the best moment. In terms of maturity, decision-making, more calm in some moments - you don't need 100 per cent speed in everything.
"It's the best moment of his career, definitely. But at the same time he's working very hard. The numbers are top, incredible."
Chelsea interim boss Calum McFarlane:
"We got into our rhythm probably a minute before the sending off and it makes the game really difficult. These things happen and you have to react.
"Going 1-0 down, it was a great reaction again and just a bit of quality from Harry Wilson at the end decides the game. We could have been a little bit more clinical. We're really disappointed but proud of the effort."
"Discipline an issue? I don't think the red card is a discipline issue, it's just a one-vs-one and he's been brought down in that situation. Rather than discipline it's looking at the structure and why we're getting countered one-vs-one. It's not like it's a high tackle, aggressive tackle or dangerous tackle. It's a one-vs-one moment. It's more structural than discipline."
