Frank Lampard confirmed Chelsea have not made any bids for Kai Havertz so far but did reveal the club remain in talks with Willian over his future.
Chelsea have already strengthened for next season by recruiting Hakim Ziyech and Timo Werner from Ajax and RB Leipzig respectively, though their spending may not be finished there.
As well as rumours of a move for Leicester City left-back Ben Chilwell, media reports have suggested the Blues are set to raid the Bundesliga again, this time to sign Havertz.
While willing to admit the Germany international is a "top player", Lampard denied Chelsea have made an offer to Bayer Leverkusen.
"He's obviously a top player but we're certainly not going to comment on other players of other teams and it cannot be our focus. No bids have gone in," the Chelsea boss told the media ahead of Thursday's Premier League clash with Manchester City.
"We have the games that we need to complete before the window opens so that's something we'll broach when it comes round. At the minute our only focus can be on the games in hand."
Lampard was more forthcoming over Willian, who has agreed to stay at Stamford Bridge for the remainder of the campaign.
The Brazil international joined Pedro in signing a short-term extension and there remains the possibility the former could stick around beyond the next few weeks.
"We're still talking with the players and Willian in particular. We're talking with him," Lampard revealed.
"It was hard for me to comment too much, obviously we announced yesterday [the deals], but I always felt confident that they would remain. They've been fantastic professionals for the club and servants in all senses.
"When you have that level of professionalism within you, I think it was a sign that they wanted to stay and see out this season at least.
"We'll carry on talking and see, but I think everybody's focus now is on these next games, the individuals themselves and obviously us as a club."
Lampard said negotiations with both Willian and Pedro – who is rumoured to be joining Roma once his contract expires – were straightforward, providing him with much-needed squad depth for the crucial run-in.
Chelsea are aiming to clinch a top-four finish in the Premier League and also have an FA Cup quarter-final against Leicester City coming up this weekend.
"I'm pleased, negotiations were relatively easy because both sides wanted the same thing," Lampard said. "Both players wanted to make sure they could see the season out with us.