Everton boss Roberto Martinez admits John Stones has been affected by interest from Chelsea.
But the manager has emphasised once again that the Toffees are not a club looking to sell their top players.
There has been talk of Chelsea preparing a third bid for Barnsley-born England defender Stones after so far having £20million and £26million offers rejected by Everton this summer.
And asked on Thursday whether the situation had affected the 21-year-old, Martinez said: "Yes, and it is something where you hope you learn from it and you get more mature and those experiences are good experiences.
"Clearly John is one of the outstanding young talents that we have in the squad and you are going to get that sort of interest from the outside.
"But all we are focused on is (Saturday's Barclays Premier League home match against) Watford. John is an Everton player and there is nothing else to comment on that."
When asked about the prospect of Chelsea coming back with an improved offer for Stones that Everton would find hard to ignore, Martinez said: "You shouldn't worry about situations you cannot affect or control.
"I said from the beginning - when you are not a club that is trying actively to sell players, the focus is just to try to be as good as we can at the weekend and see how ready we are individually and as a team.
"Everything else is stuff that does not bother me now at all."
Martinez expects Stones and winger Kevin Mirallas to be available for the campaign-opening Watford game despite the pair picking up ankle knocks in last weekend's friendly against Villarreal.
But forward Gerard Deulofeu is a doubt due to a hamstring problem, while striker Romelu Lukaku, who has had a hamstring issue of his own, will be assessed over the next 48 hours.
Tony Hibbert, Steven Pienaar, Darron Gibson, Muhamed Besic and Aiden McGeady all miss out due to injury.
Meanwhile, Martinez has indicated he would like to make three more new signings before the transfer window closes.
Deulofeu and Tom Cleverley have already arrived this summer and a loan deal for teenage River Plate midfielder Tomas Andrade looks set to be wrapped up soon.
"He is a young man with a terrific talent, who is already with us," Martinez said of Andrade.
"Hopefully we are going to agree a loan to allow him to get used to the British game. He is one for the future, not for the first team straight away."