Robey-Coleman told Bleacher Report that he expects the Rams to be able to get to the Patriots' quarterback "all over the place."
"We have to stay connected," he told the website. "And he will slowly start to reveal himself."
The Rams cornerback made headlines for his fourth-quarter hit on New Orleans Saints wide receiver Tommylee Lewis in the NFC Championship Game that wasn't penalized for pass interference or helmet-to-helmet contact (he was fined $26,739 later in the week). And now this: Robey-Coleman said age is starting to affect the 41-year-old Brady's play.
"Age has definitely taken a toll. For him to still be doing it, that's a great compliment for him. But I think that he's definitely not the same quarterback he was," Robey-Coleman told Bleacher Report. "Movement. Speed. Velocity. Arm strength. He still can sling it, but he's not slinging it as much. Whatever he was doing -- because of his age and all that -- he's not doing as much of that anymore. He's still doing the same things; he's just not doing as much of it. And sometimes, it's not the sharpest. But it still gets done."
Robey-Coleman tried to walk back his comments on Monday night at Super Bowl Opening Night, telling ESPN's Josina Anderson that his words were taken out of context.
"Well, I think everybody just made a big deal out of the situation. Tom Brady's a great quarterback. I wasn't trying to say nothing bad about him. I respect him as the GOAT. He is the legend. And I think words got misconstrued, and they got spinned out of context," he said.
He told Anderson that he's not afraid Brady will target him in Sunday's game.
"There ain't no backing down, there ain't nothing. We going to see on Sunday. He is going to throw them, I'm going to try and deflect them. That's the name of the game. As far as anything goes, I hope it be a competitive, chippy game, this is what we want," he said.
Robey-Coleman said Rams coach Sean McVay spoke with him and told him to answer all the questions regarding the situation on Monday night.
Asked for his reaction to Robey-Coleman's comments, Brady, after a notable pause, replied, "Yeah, I don't have much to add."
Brady and the Patriots have used perceived doubts about them as fuel this postseason. After the Patriots defeated the Los Angeles Chargers in the divisional round, Brady told CBS Sports during a postgame interview that "everybody thinks we suck and can't win any games" when asked about being underdogs to the Kansas City Chiefs in the AFC Championship Game.
Brady led the Patriots to an overtime victory over the Chiefs and has completed 71.1 percent of his passes for 691 yards with two touchdowns and two interceptions in New England's two playoff victories.
Robey-Coleman, who will primarily be defending Julian Edelman as the Rams' starting nickel corner, told Bleacher Report that he has a hatred for the Patriots that was developed when he played for the Buffalo Bills.
"I've got Buffalo blood running through my veins, so you know I hate these guys," Robey-Coleman told the website. "I naturally hate them. I never liked New England."
The Rams aren't alone in talking trash this week. At the Patriots' Super Bowl send-off in Foxborough, Massachusetts, on Sunday, safety Patrick Chung told the crowd, "We're gonna go out there and kick their ass, baby!"
Rams wide receiver Brandin Cooks, who played for the Patriots last season, responded at Los Angeles' send-off, telling those in attendance, "Hey Chung, we heard you talking that talk back there in Foxborough ... let's get straight," before dropping the microphone on the stage.
ESPN's Lindsey Thiry and Mike Reiss contributed to this report.