There has been talk of the Premier League champions preparing a third bid for 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 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.”