The road just keeps getting tougher for the New Orleans Saints (5-0). After an impressive win at Chicago last week, now they’re back on the road Sunday against the New England Patriots (4-1). The Patriots are 31-3 at home since 2009, but the Saints have the NFL’s best road record over that same span (23-11). Here’s What 2 Watch 4:

Brees vs. Brady: Does this one need any explanation? Two of the NFL’s all-time greatest quarterbacks will go head to head for just the fourth time in their careers and the first time since 2009. Saints quarterback Drew Brees has been playing much better than New England’s Tom Brady so far this year – in large part because injuries have plagued the Patriots’ offensive weapons. Brady had a very uncharacteristic performance in last week’s 13-6 loss at Cincinnati (18-of-38, 197 yards, no touchdowns, one interception late in the fourth quarter).

But that’s just all the more incentive for Brady to bounce back at home in Gillette Stadium. And certainly nobody in Saints camp expects anything less from the future Hall of Famer.

Also, Brady’s probably not keeping score since he has more pressing concerns to address. But Brees is actually 3-0 lifetime in these duels, dating back to his days with the San Diego Chargers.

Graham in, Gronkowski out? It sounds like we might miss out on a showdown between the NFL’s two most dynamic tight ends, since New England’s Rob Gronkowski might not be ready to return yet from offseason back and forearm surgeries. Even if he does play, he’ll likely be limited. The Saints’ Jimmy Graham, meanwhile, has been the most dominant offensive player in the NFL this year, with a league-high 593 receiving yards and six touchdowns. Defenses have tried a little bit of everything against him, but it has barely slowed him down so far. He has four consecutive 100-yard games.

“Certainly, Jimmy Graham is as good as anybody we’ve seen all year or will see in the passing game,” Patriots coach Bill Belichick said. “He is very athletic. He has great athletic ability down the field to come up with the ball. He is fast and quick and is a hard guy to match up to no matter who you put on him. If you put size on him, it’s hard to match up to his speed and quickness. If you put speed and quickness on him, it is hard to match up to his size.”

And, of course, if defenses focus too heavily on Graham, they’re liable to get burned by receiver Marques Colston or running backs Darren Sproles and Pierre Thomas in the passing game. The Saints offense is the biggest matchup headache in the league right now.

Talib on a tear: One outside-the-box possibility for the Patriots would be using physical corner Aqib Talib to help defend Graham at times. Talib (6-foot-1, 205 pounds) has been outstanding this year – arguably the Patriots’ best player. He has four interceptions and eight pass break-ups. And the Patriots have used him to shadow opponents’ top receivers more than they’ve done in the past.

The Saints are well aware of the challenges Talib can present since he began his career with the division-rival Tampa Bay Buccaneers. But this is probably the best the 27-year-old has played in his career.

“Aqib is someone who has excellent ball skills,” Saints coach Sean Payton said. “He is long, so he gets his hands on a lot of passes. You really have to be on target with where you are throwing his way. He also has very good recovery speed and so he can make up a step.

“He is playing at an elite level right now.”

Getting to Brady: Brady took a beating in last week’s loss at Cincinnati, getting sacked four times and hit several more times. That’s unusual since Brady has been one of the NFL’s least-sacked quarterbacks throughout his career, and because New England still has a healthy, veteran offensive line in place. The Saints defense, meanwhile, has done an outstanding job of pressuring the quarterback this year. The four-man front has been great, led by young breakout rushers Cameron Jordan and Junior Galette. Creative defensive coordinator Rob Ryan also threw some unexpected blitzes at the Bears last week that led to three sacks.

“I think Tom Brady’s a hard sack,” Galette said. “He just knows, he can feel the pressure. He’s real good in the pocket like Drew is. Just get rid of the ball in time. So they haven’t really been giving up too many sacks. We’ll have to find a way to get there.”