McManaman, 21, was confronted by an angry Newcastle assistant boss John Carver at half-time and figures within football have queued up to condemn the tackle.
It was initially feared Haidara had suffered a serious injury but Newcastle have since confirmed he sustained only bad bruising and soft tissue damage, although no date has yet been set for his return.
Martinez said: "I think we've been going on and on too much about it. I think it was a football incident. We lost Ryo Miyaichi a couple of weeks back and he had to go through surgery and he's out for the season. Those are incidents that happen in the game.
"I think we're taking things out of context here. I think the whole incident has been a bit of an argument about the refereeing in the game. It was a challenge with no real intent. It was an unfortunate incident that happens on a football pitch.
"I think we've been talking too much about it and it's a bit unfair on a young man to have to suffer that."