Mark Hughes expects Didier Drogba and Fernando Torres to flourish together but has warned Chelsea the partnership will take time to blossom.
The Blues' £74million strike force will start together for the second time in Monday night's west London derby at Craven Cottage.
Expectations of the duo are high following Torres' £50million transfer from Liverpool and Hughes believes they will deliver, but not overnight.
"I expect them to gel together. They are good players so it will be interesting to see how the team shapes up," said the Fulham boss.
"In the last few years with all its success, Chelsea have been based around a focal point which has been Drogba.
"He has a few others which support him as well - will that change with Torres? We will see.
"There is an expectation that the boy will play.
"I know (Chelsea manager) Carlo Ancelotti has played the diamond before so there could be a different formation now.
"Carlo has been working with formations all his life and will find the right fit, but with Torres it initially may take time."
The acquisition of Torres and fellow new signing David Luiz on transfer deadline day for a combined fee of #75million has been declared a statement of intent by Chelsea.
Hughes, who believes the Blues' main target this season is now Champions League qualification after ruling them out of the title race, believes they are under pressure to deliver.
"Chelsea have bought those two players to get into the Champions Leagues but coming in January is tough," he said.
"There is an idea that they have to make the difference. If they don't get into the Champions League then questions may be asked.
"But it isn't much of a risk signing these players because they are surrounded by quality and that can help you."
Dickson Etuhu has failed to recover from his hamstring injury so Steve Sidwell will continue to deputise in Fulham's midfield against his former club on Monday.
Sidwell has played in five matches since his arrival in January, winning three and drawing one, and Hughes is very delighted with the new arrival from Aston Villa.
"Steve has done really well so I'm really pleased with him," he said.
"Credit to him, he has not had a great deal of football and we have thrown him straight into the team because needs must.
"He is in great nick and has got up to the pace of the Premier League very quickly."
David Luiz's faith has played a big part in his journey from Sao Paolo to Stamford Bridge but he accepts physicality will be just as important as philosophy if he is to succeed at Chelsea.
Luiz, who is set to make his first start for Chelsea at Fulham, was brought up in Brazil with a firm religious background.
He believes that, as well as a strong work ethic, has stood him in good stead his career so far.
"I am a guy with a lot of faith," said the #25million January recruit.
"I believe when you have faith things will happen for you. My faith is what makes me strong and makes things happen for me.
"But I don't cross my arms and wait for God to do everything for me. You have to want it and go for it and chase your dreams.
"My dream is to be admired as a football player and as a person."
Having played his football in the leagues of Brazil and Portugal prior to his Chelsea move, Luiz also accepts he will need to get used to the rigours of the Barclays Premier League.
It is a challenge he is ready to take on.
"I knew the Premier League from TV already. I have also talked a lot to Ramires, he is always passing on positive information," Luiz said.
"It's a lot faster and more physical than where I have played before.
"But if I didn't like the physical side of the game then I would be a tennis player.
"It is not just a case of knowing what to improve but in general to become a better player."
Luiz earned rave reviews during his spell in Portugal with Benfica and was regularly linked with high-profile transfers before finally committing to Carlo Ancelotti's Blues.
Chelsea's Premier League rivals Manchester City were among those linked with the 23-year-old, but he played down their supposed interest.
He said: "I only heard about Chelsea. I never heard from any other club.
"If you believed the press and newspapers in Portugal then I was playing in a different place around the world every week.
"Now I am just pleased for the opportunity Chelsea have given me. I am pleased to be here."
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