Chelsea's British record signing Enzo Fernandez made his Premier League debut on Friday but it wasn't enough to inspire his team to victory as the Blues were held to a 0-0 draw by Fulham.
The World Cup-winning midfielder was brought in from Benfica for £107 million and he looked in good touch with precise passes and tackles.
Mykhailo Mudryk also made his Stamford Bridge bow, while Noni Madueke and David Datro Fofana came off the bench for their Premier League debuts.
Chelsea's record investment of over £300 million in the January window took the total spend on players in their first season under new ownership to over half a billion.
However, Fulham still managed to hold on, moving up one place to sixth in the table and within touching distance of European spots.
Graham Potter's team saw another chance to get closer to the top four slip by, as they sit ninth in the table, still nine points adrift of the Champions League places.
"I thought he handled himself magnificently," Potter said of Fernandez.
"You could see his quality, see what he'll bring to the team. It wasn't easy for him or for us because he hasn't been with us that long. But I'm excited with him.
"I think we have a lot of positivity and good feeling, certainly from the start of the game, and the crowd helped with that. Within the team there was a good feeling."
Potter asked for time for his expensive collection of new stars to settle down.
"New players are adapting to a new country and a new league. It's not straightforward. When the price tag is what it is questions will be asked, it's the nature of the business," said Potter.
"The decision we took in the window you can see the profile in terms of age. We feel we have a very strong group of players. We have to gel and become a really good team. That's where the work is."
Meanwhile, Potter said Pierre-Emerick Aubameyang has done "nothing wrong" after he was left out of Chelsea's Champions League squad for the rest of the season.
Aubameyang flew to Milan after being told he would not be involved in the clash with Fulham.
"He's a professional," said Potter. "I understand he'll be disappointed. It was a tough call. Pierre is just unfortunate and he'll be fighting for his place for the rest of the season.
"Whichever decision we made there was always going to be conversation about it. It was my decision. You have to make these calls. He's done nothing wrong at all."