Boston (CBS) — Both the New England Patriots and Cleveland Browns came into the season with high expectations. The undefeated Patriots have met or even exceeded them, though not quite in the way many expected. The 2-4 Browns have largely fallen short. Gillette Stadium is a tough place to begin that turnaround, but that’s what they’ll try to do Sunday. Don’t expect the Patriots to make it easy (or possible).

The big story surrounding the Patriots isn’t that they’re undefeated going into Week 8, though that is a highlight of the season so far. It’s how they got to 7-0. The defense has been stellar, leading the NFL in many of the defensive stats that matter, including yards per game (223.1), yards per play (4.0), points per game (6.9) and interceptions (18). They even compare favorably to some of the game’s best throughout history.

It’s fair to mention that the competition, which includes the Miami Dolphins, Washington Redskins and New York Jets twice, has been lacking. But that still doesn’t explain away the dominance, especially when someone like Jets quarterback Sam Darnold, who faced the Patriots defense in Week 7, admits to “seeing ghosts.”

And they’re beating offenses with a unit that lacks the star power found on other top defenses. According to James Lofton, NFL On CBS analyst and Hall Of Fame wide receiver, who has faced down his fair share of tough defenses, “the guys who are playing for the Patriots in coverage, in blitzes, in stopping the run, they pass the eyeball test. And everyone’s going ‘well, who have they played?’ Whoever they’ve played, they’ve made look really really bad. We thought the Jets, coming off an upset win over the Dallas Cowboys, were maybe going to test the Patriots a little bit. They haven’t had that test yet.”

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The preseason Browns seemed like a team that could provide that test. The mid-season Browns do not. Cleveland is 2-4 coming into Week 8, with wins over the Jets and Baltimore Ravens. Beating up on the Jets without Darnold (and backup Trevor Siemian for much of the game) is barely worth a mention. But taking down AFC North rival Baltimore Ravens may be the season’s high point so far. The underwhelming Baker Mayfield threw for 342 yards and a touchdown. Nick Chubb, the NFL’s fourth-leading rusher, ran for 165 yards and a touchdown on 20 carries.

Both of those yardage totals are team highs for the Browns, in a season that’s seen Chubb emerge as a consistent threat and Mayfield take a step back. Having Odell Beckham Jr. and Jarvis Landry hasn’t allowed the young quarterback to fulfill more of his promise. Mayfield averages 249.3 passing yards per game, which is middle of the pack. He’s also only thrown only five TDs, as compared to 11 interceptions, which is just terrible. Mayfield has struggled to deal with pressure.

Over-matched as they are, the Browns only chance against the Patriots, at least on offense, is a steady diet of Nick Chubb. As Lofton points out, “maybe having a runner who is of an elite caliber, …but also having receivers on the outside, maybe the play-action passing game gets going early. I think that can help out Baker Mayfield. And if they get on a roll, Baker Mayfield has the kind of moxy, the kind of gamesmanship to maybe try and challenge the Patriots. But it’s not going to be easy. They know it.”

His counterpart, Tom Brady, has a new weapon in his arsenal. The team traded for Mohamed Sanu, who will give them a big receiver willing to catch balls in the middle of the field. Another option in the passing game lessens the effect of Josh Gordon heading to injured reserve. And maybe Sanu can spark an offense that’s getting the job done but not living up to the high standards of past seasons. A better showing from the run game would also improve the offense; no Patriot running back has produced a 100-yard game this season. A healthy offensive line would help too, especially with sack leader Myles Garrett looking to get after Brady.

Quibbling with the Patriots’ offense’s shortcomings only goes so far when the team is undefeated. Brady and Bill Belichick know how to get them where they need to be. And that path goes through the Cleveland Browns. The Patriots won’t be derailed by a Browns team searching for answers halfway through the season.

The Patriots play the Browns Sunday @ 4:25 ET on CBS.