It was already set to be the most surreal St Patrick’s Day in modern Massachusetts memory. There would be no parade in the Irish-American stronghold of South Boston and there would be no drinking or eating in local bars and restaurants, by order of the governor. There was a pandemic to slow down, after all, and there was no time for fun and games. Literally, in fact, as the Celtics, Bruins and Red Sox had all suspended play for the foreseeable future. So things were already set to be bleak on Tuesday morning even before New England Patriots quarterback Tom Brady made the announcement that he will leave the only organization he has ever played for. In a few sentences, Brady effectively closed the book on his Patriots tenure and an entire era of Boston sports.

Nobody expected anything from Brady when the Patriots drafted him out of the University of Michigan with the 199^th pick of the 2000 NFL draft. It was inconceivable that he would develop into one of the greatest players – many will tell you the best – in NFL history. Brady began his rookie season as the fourth-string quarterback, a role that barely exists in the modern game. Head coach Bill Belichick seemed to have an idea of what he had early in Brady’s second season when he made the fateful decision to turn to him to replace an injured Drew Bledsoe, then the face of the franchise. Brady would go on to win 11 of the 14 games he started in the 2001 season, eventually leading the team to victory over the St Louis Rams in Super Bowl XXXVI. New England would clear up any further quarterback controversy by trading Bledsoe to Buffalo Bills over the offseason. From that moment on, Brady was the Patriots.

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Brady’s emergence marked the start of the Patriots dynasty, as the team would go on to be the most consistently successful team in the NFL. Under Belichick’s guidance, Brady would eventually appear in a record nine Super Bowls, winning six of them and being named MVP in four. The Patriots’ success ended up being contagious. Following the Patriots’ second Super Bowl in 2004, the Boston Red Sox reversed 86 years of agony by winning the 2004 World Series, the first of what would be four championships in the 21^st century. The Boston Celtics and Boston Bruins, after substantial title droughts, became perennial postseason threats, winning titles in 2008 and 2011 respectively.

In the midst of all this success and countless celebratory Duck Boat parades down Boylston Street, it was inevitable that Brady’s public image would transform. It soon became difficult to remember that Brady’s career began as the all-time underdog story, the sixth-round draft pick who replaced the star quarterback and led his team to an unlikely Super Bowl victory. The one-time David soon became the league’s ultimate Goliath, as the constant winning transformed the team into the most hated team in the league. A run at a perfect season in 2007, memorably shut down by Eli Manning and the New York Giants in the first of their two upset Super Bowl victories over the Pats, cemented New England’s role as heels. That role was exacerbated by a series of cheating scandals that called into question the legitimacy of the Patriots dynasty. Brady’s career has not remained untainted as the NFL suspended him for four games at the start of the 2016 season for using improperly inflated footballs.

Outside of New England, there will probably always be something of a black mark on Brady’s career. Inside of New England, the main thing fans took away from the “Deflategate” scandal was that the quarterback “stuck it to” NFL Commissioner Roger Goodell by coming back from his suspension to win his fifth Super Bowl, adding a sixth just two years later. If anything, the negative press caused fans to rally around Brady even harder. As popular opinion built against the Patriots over the years, an “Us v Them” narrative began to form among Boston fans. “They hate us because they ain’t us,” became a constant refrain and Tom Brady was very much Us.

Until now, that is. Brady leaving the Patriots marks the decisive end of an era, one that would be shocking if the writing hadn’t been on the wall over the course of the 2019 season. After years of holding off Father Time, the 42-year-old Brady was starting to show his age over the last year – for one of the few times in his career he wasn’t even chosen for the Pro Bowl – and his disappointing offensive year was a key reason why the Patriots ended up losing to the Tennessee Titans in the first-round of the playoffs. Something that had worked so well for so long just couldn’t function anymore, and now free agency has torn Brady and the team apart.

So where do the Patriots go from here? It’s possible that losing Brady could end up forcing the Patriots to move onto a brand new era of success. Bill Belichick has won six championships with the team – and has established himself as one of the greatest head coaches in NFL history, despite his sometimes ethically dubious methods – so one would think that there would be no trails left for him to blaze. Yet, one thing has always hung over Belichick’s success in New England: how much of it was because of his “genius” and how much was it was that he had Brady. If he could win one last Super Bowl with a new quarterback, it would go a long way towards settling that argument. Maybe it will turn out that the Patriots dynasty wasn’t as much about Brady as it seemed.

But another title in the near future feels highly unlikely. Brady and Belichick represented a perfect football marriage where the sum was ultimately greater than the parts. Even a declining Brady will prove nearly impossible to replace. The Patriots should still be competitive going forward, but it’s hard to avoid the feeling that a golden age of Boston sports has come to a sudden end.