Erling Haaland's winning goal in Sunday's Manchester derby has left a trail of unanswered questions — even after refereeing body Pro Ref admitted to an "error of judgement" in allowing it to stand.

Manchester City defeated Manchester United 1-0 at Old Trafford, but the decisive strike remains mired in controversy after VAR overturned an on-field offside decision to award the goal.

What Pro Ref said — and didn't say

Pro Ref — the Professional Game Referees, formerly known as the PGMOL — confirmed late on Sunday that a mistake had been made. Their statement acknowledged that Enzo Fernandez was in an offside position when he attempted to play the ball before it reached Haaland, and that the goal should have remained disallowed.

The statement read: "On this occasion, the VAR did not recognise the likely impact of his position." Yet it stopped well short of explaining why VAR failed to judge that a player six yards from goal, making a diving header, was not considered to have impacted — or potentially impacted — play.

Did VAR get distracted by the wrong question?

The most plausible explanation is that the VAR became fixated on whether Fernandez actually touched the ball — a question that, under the laws of the game, is irrelevant. A player can be offside regardless of whether he makes contact with the ball.

Match Centre's mid-game post on X stated: "The VAR also deemed that while in an offside position, Fernandez didn't play the ball." Sky Sports' broadcast replays appeared to show the VAR team scrutinising precisely that question during the review.

Why an on-field review should have been called

According to Pro Ref, the original on-field offside flag was raised against Haaland — who was, in fact, onside. VAR then correctly identified Fernandez as being offside. However, because the on-field decision cited the wrong player, VAR could not unilaterally confirm the goal should be ruled out for a different reason.

The correct procedure, as Pro Ref outlined, was for VAR Matt Donohue to request that referee Michael Oliver conduct an on-field review. Oliver would then have been asked to make a subjective judgement on whether Fernandez's position impacted play. That step was never taken.

The goalkeeper was affected too

Replays also revealed that Manchester United goalkeeper Lammens reacted to Fernandez's attempted header, raising his arms in anticipation and losing his balance — precisely as Haaland struck the ball. Nevertheless, Pro Ref's position is that the goal should have been disallowed regardless of any effect on Lammens, because Fernandez had already impacted a Manchester United outfield player, identified in the statement as Martinez.

Other questions left open

Haaland's goal was scored at 59' 24". Play did not restart until 63' 15" — a delay of nearly four minutes — yet only five minutes of added time were played at the end of the half, raising further questions about whether officials accounted for the lengthy VAR check when setting stoppage time.

Meanwhile, the Premier League's semi-automated offside technology, introduced this season, provides a kick-point graphic rather than the manually drawn lines viewers were accustomed to — a change that left many watching at home unable to follow the review in real time.