"Anthony probably came back a little bit too early," Brown told Hull's website.
"He wanted to play against Newcastle and he finished that game in a little bit of distress with regards to the injury.
"We rested him on Monday, Tuesday and Wednesday last week when he trained with the physio.
"On Thursday and Friday, he felt a little bit of discomfort and that is why he didn't play on Sunday.
"It's all about the physio getting to know the bodies and the mentalities of the new players that have come in. He is getting to grips with that.