Alistair Johnston admitted his side were not good enough during their 3-0 defeat to Rangers, before condemning the late-gate incident that saw teammate Arne Engels hit with a coin thrown from the crowd.
Johnston said he's played football in places like Central America where throwing missiles onto the pitch is more commonplace, but said it's always disappointing when it happens.
During his post-match press conference at Ibrox, he said: "I saw that [Engels] got hit just above the eye there. It's an unfortunate situation.
"We're just lucky that it didn't hit him right in the eye… I've played in some other places in Central America where they're throwing more than just coins at you.
"You feel pretty safe. It's unfortunate. Ideally, you don't want anything being thrown on the pitch. It's one thing, you know, the words and the chants, whatever. You can get through that.
"But yeah, you just hope that everyone respects the players on the pitch no matter what team they play for."
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When asked by journalists if he was aware of other missiles being thrown onto the pitch, Johnston added: "No, I was not. But again, it's something that unfortunately happens. And again, in an ideal world, it's not happening.
"That's the unfortunate case where it hits someone. And look, if that hits them in the eye, it's probably a pretty serious matter. So I just caution everyone just to be smart.
"Again, it's humans out there. It's someone's son. So let's just refrain from chucking things at guys' heads, ideally."
