20 years on, it remains the greatest single-season achievement in English football’s history. But what would Manchester United’s treble of 1999 look like under a 21st century microscope?

In partnership with StatsBomb, The Independent has analysed three key games in United’s run-in in the hope of offering fresh perspective and insight on an iconic team and a historic achievement.

First up, not only the most entertaining game of United’s season, but a bona fide modern classic: the FA Cup semi-final replay against Arsenal, won by Ryan Giggs’ spectacular extra-time goal.

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Arsenal 1-2 Manchester United (aet)

FA Cup semi-final replay

14 April 1999

Villa Park, Birmingham

Match statistics

Click on the images to expand

Match statistics for Arsenal 1-2 Manchester United (StatsBomb)

xG totals

As the graph shows, Arsenal ‘won’ the xG battle with 2.51 to United’s 1.62. This is a significant gap, enough for the model to predict that Arsenal would win and progress to Wembley 59 per cent of the time.

The shape of the game, as shown by cumulative expected goal values of all shots (StatsBomb)

However, that difference between the two sides is largely accounted for by one moment – Dennis Bergkamp’s missed, 90th-minute penalty, worth 0.76 xG alone. Otherwise, this was a tightly-contested game of high-quality drama and low-quality chances.

Shot locations

Shot locations, with descriptive information of shot type (StatsBomb)

Bergkamp’s penalty was Arsenal’s best by some distance. No other shot at Peter Schmeichel’s goal registered more than 0.24 xG. Only Emmanuel Petit and Nicolas Anelka fashioned half-decent opportunities to score.

United had far fewer shots than Arsenal – 16 to their 27 – but the locations of their attempts were generally better and they found joy on the break. The best of their chances came in the second half, while still 1-0 up and in quick succession.

The first fell to Ole Gunnar Solskjaer, who beat Arsenal’s famous offside trap but put a 0.43 xG chance wide. Jesper Blomqvist hit a 0.32 opening at David Seaman soon after. Had either scored at that point, it would have been a very different, less memorable evening.

A look at the shot locations shows a high volume taken from outside the box by both sides. These were either blocked (grey) or low-quality (blue) attempts that stood little chance of producing a goal. And yet, two of them did.

Beckham’s goal

Beckham’s opening goal vs Arsenal (StatsBomb)

Take the opening goal, for example. The StatsBomb model ranks David Beckham’s shot from range of around 30 yards as a 0.02 xG chance – roughly the same value as Vincent Kompany’s recent wonder-goal against Leicester City.

And what’s more, the goal only comes about because Patrick Vieira fails with a 0.04 xG volley from long range seconds earlier. Peter Schmeichel collects Vieira’s shot, launches the ball back upfield and after a one-two with Teddy Sheringham, Beckham scores.

It is 30 seconds of football which sums up why this particular game is so fondly remembered and why we rarely see full-throttle, end-to-end contests between two teams shooting on sight 20 years later.

Fewer and fewer modern-day coaches would encourage Vieira’s audacious attempt because firstly, it stood little chance of coming off and secondly, it was more likely to leave Arsenal open to a quick counter.

Bergkamp’s penalty

Visualisation of shots on target (Getty)

Of course, Arsenal would eventually equalise through a speculative attempt from range anyway.

Bergkamp’s equaliser – which was helped past Schmeichel by a deflection off Jaap Stam – would be scored around one in every 100 times according to StatsBomb’s model. It was even more unlikely than Beckham’s.

United were second-best from thereon, even before being reduced to 10 men. Sir Alex Ferguson’s side failed to add significantly to their cumulative xG, while Arsenal chipped away, looking for the breakthrough to finish their tiring rivals off.

The chance came in the 92nd minute, when Phil Neville brought Ray Parlour down inside the penalty area. But Bergkamp’s spot-kick was placed in the centre-right of the goal, several yards shy of the corner, and at a comfortable height for Schmeichel.

A penalty is valued at 0.76 xG, as around three-quarters of penalties are scored. Post-shot xG, which measures what happens after the ball leaves a player’s foot, values Bergkamp’s attempt at 0.66 xG. In other words, less than average. It was the last Bergkamp ever took.

Giggs’ winner

Giggs’ winning goal in extra time (StatsBomb)

The most iconic moment was still to come, of course. Giggs’ winning goal – one of the greatest in FA Cup history – was an extremely difficult one to score, even after beating four Arsenal players on a run which started inside his own half.

Having surged past Vieira, Martin Keown and Lee Dixon, Giggs finds himself in quite an unfavourable position. Even when this close in, scoring from a tight angle is hard. It is harder still after a long, mazy run at pace through English football’s meanest defence.

What’s more, Giggs is up against a goalkeeper in Seaman whose feet are set and who is narrowing the angle. Seaman leaves very little space between himself and his near post. Tony Adams is charging across too, ready to slide and block.

All these factors contribute to a surprisingly low xG value of 0.07 on Giggs’ shot, but perhaps that is only surprising because we all know what happens next. Seaman stops him from going either side, the pass in the centre to Paul Scholes is blocked off, so Giggs decides to go over the top.

Manchester United 2018-19 player ratings Show all 26 1 /26 Manchester United 2018-19 player ratings Manchester United 2018-19 player ratings Manchester United 2018/19 player ratings How did Manchester United's players perform this season? After a difficult campaign, we give each member of the squad a rating out of 10. AFP/Getty Images Manchester United 2018-19 player ratings David de Gea - 4/10 A poor year by an outstanding goalkeeper’s standards. Confidence seemed to be affected by errors and his limitations in distribution were sometimes exposed. Getty Manchester United 2018-19 player ratings Sergio Romero - 6/10 A dependable back-up in the domestic cups. Sent off in defeat to Derby in September, but did not let Solskjaer down in the run to the FA Cup quarter-finals. Getty Manchester United 2018-19 player ratings Victor Lindelof - 7/10 One of a few to emerge with any credit, even if he was more consistent in the first half of the campaign. His reputation enhanced, he is the only central defender whose place is secure. Getty Manchester United 2018-19 player ratings Phil Jones - 4/10 Unfairly targeted at times but still, eight years on from his arrival, far too injury prone and inconsistent to be depended upon. Even so, signed a new contract until 2023. Getty Manchester United 2018-19 player ratings Chris Smalling - 6/10 Led the defence well during Solskjaer’s first few weeks and months in charge but, like Jones, his limitations are well known by now. Getty Manchester United 2018-19 player ratings Luke Shaw - 7/10 Found confidence, consistency and finally established himself as a first-team regular. It proved enough to be named Player of the Year. Manchester United 2018-19 player ratings Diogo Dalot - 6/10 A new arrival from Porto, Dalot showed glimpses of the potential which persuaded United to part with £19m. A solid if unspectacular debut year should now be built upon. Getty Images Manchester United 2018-19 player ratings Ashley Young - 4/10 Not the long-term solution to the right-back position yet a first-team regular with a chance of being the next club captain. Loyal and diligent but is he still the best option? Getty Manchester United 2018-19 player ratings Antonio Valencia - 3/10 Ends his long United career out of favour, but underwhelmed in the few appearances he made regardless. A correct decision to let him go. Manchester United 2018-19 player ratings Matteo Darmian - 5/10 Somehow still at the club, yet did not totally disgrace himself when called upon for a handful of appearances. Needs to be moved on, nevertheless. Getty Manchester United 2018-19 player ratings Eric Bailly - 3/10 A bad year a player whose Old Trafford career undeniably went backwards. Embarrassed with early substitutions against Newcastle and Paris Saint-Germain. Getty Manchester United 2018-19 player ratings Marcos Rojo - 2/10 The curious United career of Rojo continues. Made just eight appearances, spent long spells sidelined with unspecified injuries, all less than a year after signing a new contract. Getty Manchester United 2018-19 player ratings Nemanja Matic - 4/10 First-choice at the base of midfield yet lacks the speed or technical ability of others in the same position at top clubs. Getty Manchester United 2018-19 player ratings Ander Herrera - 7/10 Impressed when employed as a destroyer and runner type in central midfield by Solskjaer, yet a new contract could not be agreed. Leaves after one of his better years. Getty Manchester United 2018-19 player ratings Paul Pogba - 6/10 Far from the worst offender but another season not commensurate to his talent. His 17 goals from midfield included eight penalties and another three spot-kicks were missed. AFP/Getty Images Manchester United 2018-19 player ratings Scott McTominay - 7/10 Proved himself to be first-team squad material with a series of good performances in the second half of the campaign. Most improved player by some distance. Getty Manchester United 2018-19 player ratings Fred - 4/10 A difficult first year in Manchester for United’s fourth-most expensive signing ever. Looked woefully off-the-pace at times, only moderately effective at others. Needs a big second season. Manchester United 2018-19 player ratings Juan Mata - 5/10 A popular figure but did little to force the club into awarding him a new contract. May leave having rarely been used effectively in his best role and might even regret the wasted years. Manchester United 2018-19 player ratings Andreas Pereira - 5/10 Strike against Southampton won club’s goal of the season award but offered little else to suggest that he is a long-term answer in midfield. Getty Manchester United 2018-19 player ratings Jesse Lingard - 4/10 After an impressive 2017-18, just five goals and four assists is a poor return. Injuries did not help but performances were inconsistent. Getty Manchester United 2018-19 player ratings Anthony Martial - 5/10 The talent is there but is too rarely displayed. Enjoyed a run of good form around October and Christmas, but fell quiet once he had signed a new contract. Getty Manchester United 2018-19 player ratings Alexis Sanchez - 2/10 The Premier League’s best-paid player was not worth a penny. Difficult to find any positives in a wretched season, bar that late goal which may have only prolonged Mourinho’s stay. Getty Manchester United 2018-19 player ratings Romelu Lukaku - 5/10 15 goals in 45 appearances for a £75m striker cannot be dressed up as anything but a disappointment. A player that neither Mourinho or Solskjaer have catered towards. Getty Manchester United 2018-19 player ratings Marcus Rashford - 5/10 Despite enjoying a run of form in the mid-part of the campaign, that was lost by the end. Questions remains over whether he will reach the elite bracket of strikers. Getty Manchester United 2018-19 player ratings Ole Gunnar Solskjaer - 5/10 A promising start, a worrying end. Several odd decisions and a tactical inconsistency have caused concern, but he should only be fully judged with a pre-season behind him. PA

Verdict

Two decades on, the most striking thing to note from this game’s underlying numbers is how both sides – despite being packed with quality and committed to fast, counter-attacking football – struggled to create many clear-cut chances.

And yet, even so, there were three goals, a missed penalty and no less than 43 shots. Of those three goals, two were scored from outside the box. The third started in the player’s own half and ended at an inauspicious angle.

The statistical likelihood of one of those three goals being scored is small, let alone all three. That, ultimately, is why this is remembered as the greatest instalment of one of English football’s greatest rivalries and a key moment in United’s treble success.

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