Patriots will look to fix what went wrong in Miami in time for Sunday's game at Pittsburgh
That's why it was so unexpected this season to see New England putter to a 2-2 start and drop to the bottom of the NFL's defensive rankings after allowing 30 or more points in three of those games.
That changed during an eight-game win streak in which the Patriots' defense was the league's stingiest unit, allowing just 11.8 points per game.
The turnaround also came despite the Patriots losing linebacker Dont'a Hightower to a season-ending injury, and others for various periods of time along the way.
But that run of fortune was halted with Monday's 27-20 setback at Miami . It was the Patriots' first loss since Oct. 1 and their first on the road since a 20-10 defeat at Miami in the 2015 season finale.
Jay Cutler earned his first win against the Patriots, throwing for 263 yards and three touchdowns. Kenyan Drake had 114 yards rushing, becoming just the third running back to reach 100 yards against New England's defense this season.
The defeat also came with a physical price. Defensive lineman Alan Branch left the game with a knee injury, and safety Patrick Chung limped off in the final minute.
It's poor timing for a group that was already without sack leader Trey Flowers (ribs) and linebacker Kyle Van Noy (calf).
It could make for an even more depleted defense for Sunday's pivotal road matchup against Pittsburgh.
The Steelers (11-2) lead New England (10-3) in the race for the AFC's best record. A win by Pittsburgh and a Jacksonville loss would give the Steelers home-field advantage throughout the AFC playoffs.
Even though the Patriots knew going into the Miami game that the stakes would be high the following week, safety Devin McCourty scoffed at the idea of their shortcomings being the result of looking ahead to Pittsburgh.
"You've got a championship on the line. That's not a trap game. We didn't execute as well as we needed to against another team that's fighting for their playoff berth, too," he said.
"It's just that point in the season where if you don't play at your highest level you'll lose. Everyone's out here playing for something."
McCourty was one of the few bright spots against Miami, earning his third career sack, and first since 2015.
Patriots defensive coordinator Matt Patricia has excelled this season at getting the best out of a young group that has been forced to integrate several new contributors.
Defensive end Eric Lee has earned his first career starts in back-to-back weeks. Linebacker Jonathan Freeny also played in his first game for the Patriots this season on Sunday after re-signing with the team earlier in the week.
Patricia said the challenges this week will be amplified in the hostile confines of Heinz Field.
"It's everything you want a football environment to be when you're a visitor in that stadium," Patricia said.
Belichick acknowledged there is a balance in correcting their mistakes from the Miami loss and turning the page to a Pittsburgh offense that has a vastly different scheme.
"We have to spend a little bit of time on the things that we need to make sure that we correct and address, or we'll see them again and they'll be a problem again," Belichick said.
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