You'd think that there's not much room for improvement when you allow just three points to the second-highest scoring offense in football during Super Bowl LIII. Yet, here the Patriots are with a defense that has the potential to be even better than that near shutout performance en-route to a sixth Lombardi Trophy. 

Bill Belichick-led defenses playing well isn't anything particularly new. After all, the last time they were outside the top 10 in the league in fewest points allowed was in 2011, so there's essentially been an entire decade where New England has kept the scoring to a minimum. 

With that said, this year feels a bit different. 

Despite having the notable loss of Trey Flowers in free agency, New England's additions to the defensive side of the ball far outweigh their losses. Make no mistake, Flowers leaving the Patriots is a tough blow. He was the third highest-graded edge defender in the league in 2018 and finished 10th in total pressures, according to Pro Football Focus

While Flowers certainly can ball (his five-year, $90 million deal with the Lions is proof of that), the Pats did just about as good as you can in replacing him with their trade for fellow defensive end Michael Bennett. 

The 33-year-old can do a lot of same things Flowers did during his time with New England, so he should fit in quite seamlessly, but will likely see more time inside than he's accustomed to. 

His 73 QB hits over the last three seasons is second only to Rams superstar Aaron Donald. He also was fifth among edge defenders with 68 pressures in 2018, four spots higher than Flowers, per PFF. Among edge defenders, only Von Miller and Khalil Mack have totaled more pressures than Bennett since 2014. 

So, with their biggest offseason loss on the defensive side of the ball, they did extremely well at filling that spot. Let's take a look at the projected depth chart before we go in-depth:

DE Deatrich Wise Jr. Chase Winovich
DT Danny Shelton Adam Butler
DT Lawrence Guy Byron Cowart
DE Michael Bennett John Simon
LB Kyle Van Noy Jamie Collins Sr.
LB Ja'Whaun Bentley Calvin Munson
LB Dont'a Hightower

LCB Jason McCourty J.C. Jackson Joejuan Williams
RCB Stephon Gilmore Jonathan Jones Keion Crossen
FS Devin McCourty Duron Harmon Nate Ebner
SS Patrick Chung Terrence Brooks

(Find the Patriots' projected offensive depth chart here.)

Changes to note

New England also saw cornerback Eric Rowe, defensive tackle Malcom Brown and defensive end Adrian Clayborn leave Foxborough this offseason, but that group doesn't include anything true significant losses as there are plenty of players on the roster that will fill those shoes rather easily.

The Patriots did welcome back Jamie Collins. This will be the linebacker's second stint in New England after spending the two and a half seasons with the Cleveland Browns. If Collins follows a similar path that Patrick Chung did in 2014 during his second stint with the Pats, where he was a more efficient and impactful player, it should be even more productive than the first. 

Collins notched 104 tackles and four sacks last season and should be a pretty versatile weapon all along New England's front seven, which will help with the loss of Clayborn and then some. 

As for the NFL Draft, the highlights are the additions of corner Joejuan Williams, defensive end Chase Winovich and defensive tackle Byron Cowart. Winovich will likely have the most productive rookie season in 2019 as the second-rounder in Williams could be behind what is an extremely deep secondary. Coward, a fifth round pick out of Maryland, also has been making noise in limited action this preseason. 

And those are just the additions. 

Secondary is primary

Arguably the deepest area regarding the reining Super Bowl champs is the secondary. At corner, Stephon Gilmore is coming off his first All-Pro season, the team re-signed Jason McCourty and undrafted gem from 2018 in J.C. Jackson is looking to make an even bigger leap this year. 

If Gilmore and McCourty have similar production in 2019, while Jackson takes a second year leap, That's quite the one-two-three punch. During his rookie season, Jackson allowed a league-low 42.0 passer rating (minimum of 200+ cover snaps), per PFF. If you combine that with Gilmore's NFL best 29 forced incompletions throughout all of 2018 (including playoffs) and McCourty's eighth ranked coverage grade of 83.3, this is about as shutdown of a unit as you can get. 

That's not even mentioning whatever second-round pick Joejuan Williams can give this position in his rookie year or what Duke Dawson or Keion Crossen can deliver in Year 2. 

At safety, Devin McCourty, Patrick Chung and Duron Harmon are a veteran group that has been there and won three Lombardis. 

Power in the box

Linebacker is the second-deepest group, headlined by another veteran cast of Dont'a Hightower, Kyle Van Noy, Elandon Roberts and Collins. 

You essentially know what you're going to get out of that group, but the most compelling figure in this unit is second-year linebacker Ja'Whaun Bentley. He missed most of last season due to a torn bicep, but in his short showing impressed. In three games, he totaled nine tackles and one interception, while also being given play-calling responsibilities with the green dot on his helmet. The fact that the Patriots were willing to give him that role essentially out of the gate is telling. Now that he's healthy, he could be in for a breakout season to make this group even deeper. 

As we mentioned above, Flowers and Bennett are the biggest change to the defensive line. Adam Butler could see more opportunity now that Mike Pennel has been released and Deatrich Wise along with John Simon, who re-signed with the club this offseason, should also see a bump in playing time now that Flowers is gone. 

Meet the new boss

Finally, let's look at the coaching. For the second season in the row, the Patriots will be working with a new defensive coordinator. 

In 2018, Matt Patricia departed the franchise to become the head coach of the Detroit Lions and this offseason saw de facto defensive coordinator Brian Flores accept the Miami Dolphins head coaching job. For a moment, it appeared like former Ohio State defensive coordinator Greg Schiano was going to accept the job, but he walked away from the team before formally accepting. 

Linebackers coach Jerod Mayo has been seen calling out the defensive plays throughout the summer, but most of the responsibility will simply fall on the shoulders of Bill Belichick. That's an improvement to whoever you compare him to, as Belichick simply is the best to ever do it and defense is his bread and butter. 

If he has his hands even deeper in the pot in 2019, that's even more reason to think this unit will go gangbusters.