The now-departed striker claimed on Wednesday that he was left with no choice but to leave Tynecastle after he and his family suffered racial abuse in the stands.
However that came as a surprise to Smith and his team-mates, who had no prior knowledge of the situation.
Craig Levein expressed his disappointment and embarrassment on Thursday that Goncalves, who has now moved to Uzbekistan, did not feel he could approach his manager with the issue.
Smith said Goncalves kept it to himself: “I’ve had a chat with a few of the boys and even they didn’t know.
“The first I heard of it was yesterday, so if it has happened Isma has kept it under his hat and to be honest if it has happened, the vast majority of Hearts fans are not like that and it’s one or two narrow-minded people who have done it.
“It’s disrespectful and there is no space for it in football.”
He added: “It’s for him to deal with. People deal with things in different ways. If it has happened then he kept it under his hat and it’s up to him and his family to deal with it.
“The club are dealing with it in their own way, and will find out if it has happened and will deal with it.
“I don’t think any of the players thought any of the fans would do anything like that and there’s no place for racism in football.”
Despite the allegations of racial abuse, Smith remains confident it is restricted to a small minority of the Hearts support and was still full of praise for the fans ahead of the trip to face Ross County on Saturday.
He said: “All the fans I have spoken to are brilliant.
“We’re on a great run now and they’re all behind us and the attendances are up and it’s a great place to be at the minute.”