The crumbling of a dynasty: How can the New England Patriots navigate the post-Tom Brady era?

The New England Patriots have known nothing but success for the two decades that they had Tom Brady on their roster. But with the six-time Super Bowl winner having made his exit, has time run out on Bill Belichick's team?

NFL roster assembly is often an exercise in plugging gaps. The free agency and draft systems afford teams opportunities each season to fill holes which became evident the year before, meaning that – as draft position is designated by their final position in the prior season – underperforming teams are given the pick of the litter when it comes to the rookies hoping to make a name for themselves on the gridiron. 

The Cincinnati Bengals, by virtue of being the consensus worst team in the NFL last year, will get the first pick in this April's NFL draft, where they are almost certain to select LSU quarterback Joe Burrow - the young gunslinger poised to take the league by storm. It is a move they hope will provide the team with the foundation of a dependable starting quarterback, around whom they can build a team. 

The draft system, as the name suggests, is something of a lottery. Teams can never be certain what they are going to get and whether or not the work on the practice field will mirror the carefully selected clips from a young player's highlight reel. 

Every once in a while, though, teams strike gold. 

Twenty years ago, the New England Patriots selected a gangly, unimpressive-looking quarterback with the 199th pick of the draft. Brade had been passed over by literally every team in the NFL on multiple occasions by that point in the draft. However, Patriots coach Bill Belichick liked what he saw and the deal was struck. It became the most famous draft selection in NFL history. 

Brady's achievements in New England need little repeating here as it is among the most sustained and impressive eras of success a sports team of any type has experienced. Nine Super Bowl appearances (and six wins) followed, with Brady very much the lieutenant on the field to Belichick's five-star general but now that this legendary partnership has been cleaved in twain what exactly does this mean for the NFL's most successful franchise so far this century?

While Belichick remains in post, a significant part of the Patriots DNA will head with Tom Brady to his new home at the Tampa Bay Buccaneers. To draw a comparison from elsewhere in sport, this would mirror Sir Alex Ferguson leaving Manchester United only for the team to struggle through subsequent seasons without his leadership.

From David Moyes, to Louis van Gaal, Jose Mourinho and now Ole Gunnar Solskjaer, United have yet to fully recapture the aura of invincibility that Ferguson imbibed in his teams - so spare a thought for Jarrett Stidham, the 23-year-old fourth-round draft selection who is now tasked with filling the boots of the greatest quarterback of all time. 

Stidham – who has completed just two career passes in a very brief appearance on the team last year – faces an unenviable task because, even if you subtract Brady from the equation, the Patriots roster is as weak as it has been at any point during Belichick's tenure.

Add to that the departure of key defensive figures Kyle Van Noy and Jamie Collins, and it is easy to come to the conclusion that the forecast isn't rosy in Massachusetts. 

The remaining free agency period and next month's draft will offer some further clues to how the Patriots will line-up when the season kicks off in several months time. But this time, they will enter a season for the first time since 1993 with uncertainty over the identity of their starting quarterback.

Whomever the Patriots end up installing as Brady's replacement, one thing seems certain. The newcomer will find it almost impossible to adequately replace the man who just left.