Chelsea head coach Frank Lampard says new signings Hakim Ziyech and Ben Chilwell will miss Monday's match against Brighton, while Thiago Silva is unlikely to play.
The Blues start their Premier League season away to the Seagulls on Monday Night Football - live on Sky Sports - but Lampard is set to be without several of his new arrivals.
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Attacking midfielder Ziyech and left-back Chilwell will not be fit enough to feature, while Brazil defender Silva is not yet training with the rest of the first team.
"Hakim Ziyech took an injury to a knee against Brighton so won't be fit. Hopefully it's a matter of weeks, a couple of weeks but we have to see," Lampard said at Thursday's press conference.
"Ben Chilwell is working towards fitness and improved this week. He's going in the right direction but won't be ready for Brighton.
"Thiago is in London but not training with us until the weekend, so I doubt he's in contention for the game."
Lampard has been boosted, though, by the return to fitness of Christian Pulisic and Cesar Azpilicueta, who both sustained hamstring injuries in last season's FA Cup final defeat to Arsenal.
He added: "I am certainly very happy to have them both back. They have trained since yesterday and are in contention for Monday.
"The way they are training and the attitudes they have looks like they are over their injuries. We'll have to manage it."
Lampard coy on Mendy
Chelsea remain in talks with Rennes over a deal to sign £18m-rated Rennes goalkeeper Edouard Mendy.
Lampard is keen to provide competition for Kepa Arrizabalaga - who is yet to convince following his £72m arrival two years ago - but refused to disclose whether or not the club are close to reaching an agreement for Mendy.
"It's a situation I don't want to draw on. He is a Rennes player," Lampard said.
'I thrive under pressure'
Chelsea have thrown huge financial backing behind Lampard this summer, having already spent over £200m on seven players.
As well as Ziyech, Chilwell and Silva, Chelsea have signed highly-rated Germany internationals Timo Werner and Kai Havertz.
Lampard has also brought in France U21 international Malang Sarr - who will be loaned out for the season - and teenage defender Xavier Mbuyamba.
Despite the amount of money he's spent so far and the increase in expectations, Lampard insists he is ready for the challenge.
"The pressure on me to do better should be standard," he said. "I don't want to talk about statements.
"Last year we were very happy for Champions League places, we were very joined up in the business we wanted to do. The work starts now. It's been a bit of a broken pre-season, but you have to work hard very quickly.
"I hope Chelsea fans are excited because we have brought in a high level of players, but I know what it takes to win the Premier League.
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"Manchester City and Liverpool have run it over a few years. We know expectations are there, but we want to improve and not get ahead of ourselves.
"I am surprised if you didn't think I wasn't under pressure last season. I thrive off the pressures. It's what I love doing.
"I didn't come in the job to fight for fourth place or bring academy players in, I came here to win.
"Last year we couldn't recruit and this year the club have made the decision to bring in players. It changes the landscape and we're ready to work."
There were only modest expectations for Frank Lampard's first season at Chelsea, especially when joining with the club under a transfer embargo. Now, armed with an expensive new squad, the pressure will be on to deliver.
From the moment he announced plans to go into coaching, Lampard was always destined for the top job at Chelsea, but his first season was not without its complications. He was unable to make a signing in his first summer, instead choosing to promote from within, showcasing talents such as Mason Mount, Billy Gilmour and Tammy Abraham.
With no new bodies in January either - despite the lifted embargo - Lampard still guided his side to a top-four finish and into the FA Cup final. He showed what he could do without Roman Abramovich's money thrown behind him...but with the Russian owner now doing just that, and Chelsea the big spenders this summer, the stakes have been massively raised for the 2020/21 campaign.
All the latest news, analysis and rumours from the window in one place.
The men's summer transfer window will run for 10 weeks from July 27 and close at 11pm on October 5.
A domestic-only window for trades between the Premier League and EFL then runs from October 5 and closes on Friday, October 16 at 5pm.
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