An incensed Talau approached Hastings at fulltime after the Knights claimed a 14-12 victory at Leichhardt Oval.
The pair were teammates last season but Talau, who was hit high by Hastings and ruled out with a concussion, was furious.
Tigers prop David Klemmer also gave Hastings a piece of his mind, while coach Tim Sheens later said Talau had sustained a broken nose.
"It was a heat of the moment thing," Hastings said.
"I went to apologise, I didn't realise in the game I collected him high.
"I just tried to do the right thing at the end of the game by going up to say sorry, in the heat of the battle he was still angry, which I fully appreciate.
"No one wants to get hit in the head and they ruled him out for the game too, so I am remorseful; there was no intent. I can see why he would be frustrated."
Klemmer, who was part of a swap deal with Hastings over the summer, then pushed the Knights playmaker away.
A security guard stepped in before Hastings was escorted away by Knights football manager Peter Parr.
"He (Klemmer) is renowned for being a great teammate and he stuck up for his teammate," Hastings said.
"I had no issue with Tommy's reaction. I would be pretty filthy myself.
"Sometimes in contact sports things go wrong. Last year I was out for six months with an accident ... but I am really apologetic."
Hastings was placed on report at the time and is likely to be charged by the NRL's match review committee on Monday.Â
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