The forward pass
Imagine a more stop-start version of rugby, where a player takes the ball and sprints directly into a scrum before the two teams reset and do it again.
You’ve just imagined an NFL game from the 1920s.
In the early years of the league, quarterbacks could only throw the ball forward from within five yards of the line of scrimmage, so pass plays were rare.
A 1933 rule change, however – inspired by the NFL’s desire to separate itself from the college game – allowed forward passes from anywhere behind the line, a decision that transformed the sport into the high-flying spectacle it is now.
In the 1932 season, no quarterback threw for more than 640 yards or nine touchdowns.
In 2015, Drew Brees of the New Orleans Saints - currently 10/1 to be named 2019 MVP in the NFL betting - threw for 505 yards and seven touchdowns. In one game.
The draft
Parity is everything in the NFL.
That a team can go from bottom dwellers to title winners in just a couple of seasons is a major part of why the league is so exciting.
That volatility is largely thanks to the draft.
Prior to 1936, teams would scramble to sign amateur players in chaotic bidding wars, driving up salaries for unproven college graduates who would hold out for the biggest offer.
So, in a bid to restore competitive balance and take leverage away from the players, the NFL became the first major sports league to hold an annual draft, in which franchises take turns selecting amateur players, with the worst team from the previous season picking first.
Rewarding failure in such a way might seem entirely at odds with what America claims to stand for, but the system caught on.
Every other major sports league followed suit and held their own inaugural draft within the following 30 years.
Racial integration
Segregation wasn’t outlawed in the United States until 1964, so it’s no surprise that the NFL was almost exclusively white for much of its formative years.
While a handful of black players played in the first few NFL seasons, there were none in the league between 1934 and 1946.
Then, Kenny Washington – one of the best collegiate players ever – permanently broke the race barrier by signing for the Los Angeles Rams.
The league very slowly integrated black players from there – helped by a boost from merging with the more tolerant AFL in 1970 – and as of the 2014 season the NFL’s player pool is now approximately 68 per cent African American.
The problem is by no means fixed, though.
Despite the NFL introducing the ground-breaking Rooney Rule in 2003 – which requires teams to interview at least one candidate with a minority background for every head-coaching vacancy – just three of the 32 NFL franchises have African-American head coaches as of the start of the 2019 season.
The schedule
The NFL’s early years were chaotic.
With no set schedule, franchises played against anyone they could manage to arrange a fixture against, including teams from outside of the league.
They effectively made it up as they went along, and the amount of games they played varied wildly as a result.
While some teams played 10 or more, the Muncie Flyers, who finished last, had just one fixture (which they lost).
There was no championship game back then. The title winners were voted on at a contentious end-of-season meeting of the team owners.
That’s hardly a formula for a successful league, and in 1933 the NFL finally had its inaugural title game, with the Chicago Bears beating the New York Giants.
Three years later, the league reached a point where all nine of its members played 12 games, and since 1978 the regular season has been comprised of 16 fixtures for each team.
The helmets
Looking at NFL helmets from the 1920s is terrifying, and not just because they made some players look like Hannibal Lecter.
No, what’s frightening is imagining helmet-to-helmet hits being dished out with just a layer of soft leather ‘protecting’ the skull.
The NFL gradually moved from leather skull-caps to plastic helmets with face masks in the 1940s, and by the 1950s all players wore the polymer helmets that are universal today.
The move away from leather was intended to improve player safety, but brain injuries – such as CTE – are a stain that the NFL just can’t cover up.
In 2013, around 4,500 former players sued the league for concussion-related injuries.
As a result, the NFL has pushed hard to outlaw helmet-to-helmet collisions, with penalties and fines becoming increasingly penal over the past few years.
The AFL merger
It’s not a great look for a league that likes to call its title winners “world champions” to be competing against an emerging rival with deep pockets, talented players and a more exciting style of play.
That was the case in 1959, though, when a group of wealthy owners formed the AFL and quickly threatened the NFL’s dominance by luring away some of the top college recruits with lucrative contracts.
The NFL initially ignored the younger league but eventually recognised that its talent base and profitability were both at risk and opened talks to merge the two organisations.
In 1966, a deal was agreed and a 24-team league was formed with two conferences – the AFC, featuring the former AFL franchises, and the NFC, featuring the remaining NFL franchises.
At the end of each season, the conference champions would play each other, spawning one of the biggest sporting events in the world…
The Super Bowl
You won’t find many non-basketball fans tuning into the NBA Finals, and only baseball devotees watch the World Series.
The Super Bowl, however, regularly attracts over 100 million viewers worldwide, more than any annual sporting event other than the Champions League final.
That’s impressive, considering American football is a complex game that can be tricky for casual fans to pick up and is almost exclusively played in the US.
The NFL has done a fantastic job of marketing its championship game.
Super Bowl Sunday is now essentially a national holiday, and traditions like Super Bowl parties and prop bets have spread to countries outside of the US.
The half-time show
The Who. Prince. Beyonce.
Some of the biggest musical acts in the world have produced iconic performances at the Super Bowl half-time show.
No other sporting event puts as much focus on its in-game entertainment, and there’s no doubt that part of the Super Bowl’s huge success is down to the popularity of the half-time show.
It wasn’t always the case. Until the early 1990s, the show would typically feature a marching band with a theme like A Salute to the Big Band Era or It’s a Small World.
But Michael Jackson’s iconic 1993 performance changed everything, drawing 91 million viewers and making the half-time show a coveted gig for the world’s biggest artists.
Since then, the half-time show has often been as memorable as the game itself, producing unforgettable moments like Katy Perry’s ‘Left Shark’ dance, Lady Gaga’s leap from the stadium roof and, of course, Nipplegate.
The salary cap
Aside from the draft, the salary cap is the NFL’s greatest leveller.
While sports like baseball and soccer (apologies, football fans) tend to reward the owners with the deepest pockets, the NFL sets a hard limit every year for how much each team can spend.
Following the example set by the NBA a decade earlier, the NFL introduced the cap in 1994, meaning success in the league is now almost entirely dependent on good coaching and talent evaluation.
The NFL doesn’t have a Manchester United or Real Madrid equivalent.
While the New England Patriots have dominated since 2000, their success can largely be attributed to the sustained performance of three-time MVP Tom Brady – the (almost) undisputed quarterback GOAT – and three-time Coach of the Year Bill Belichick, rather than the chequebook of Robert Kraft.
International expansion
The NBA and MLB have both played regular-season games in London in the past year, but it was the NFL that really pioneered international expansion.
Having staged a handful of exhibitions at Wembley in the 1980s and one regular-season game in Mexico in 2005, the league brought the Miami Dolphins and New York Giants over for its first ever meaningful game in the UK in 2007.
The game was truly awful. The Giants slogged to a 13-10 win in the pouring rain (classic London).
Wembley sold out instantly, though, and the huge fan support convinced the league to stage games in London every year.
The Jacksonville Jaguars – owned by Fulham owner Shahid Khan – signed a deal in 2013 to hold a home game in London every year, while the NFL have also agreed to stage at least two fixtures per season at the new Tottenham Hotspur Stadium for the next decade.
Everything is in place, then, for the league to take its most ambitious step yet – moving a team to the UK permanently.
Should the league convince the players, it could only be a matter of time until we’re watching the London Jaguars take the field.