Asked about the receiver's progress with the team since signing with the Pats last weekend, coach Bill Belichick said Friday that Brown had a "long way to go."
"Obviously, he's not familiar with our offense," Belichick said. "The systems that he's been in have been quite different. Jon [Gruden] does the West Coast offense, which there's very little carryover from their system to our system. Not bad or good -- just we've had players before. It's just not all going to carry over, and a similar thing in Pittsburgh.
"You know, he's working hard to pick it up, and we're working hard to get it to him. ... We try to get him caught up to speed as quickly as you can. It's too much ground to make up in a few days, but we do the best we can and we'll see how it goes."
The receiver was accused earlier this week of rape by former trainer Britney Taylor in a civil lawsuit filed in Florida. There is currently no criminal investigation into the accusations.
The NFL is not planning on placing Brown on the Commissioner's Exempt List ahead of Sunday's tilt. The league's investigation into the accuser's claims is just beginning, and there is not enough evidence yet to form a conclusion as to whether Brown violated the personal conduct policy, according to a league spokesman.
Brown can still be placed on the exempt list at a later date. The league is expected to meet with his accuser next week.
For now, the receiver is free to play football, and it appears he'll do so on Sunday afternoon.