When the Report Is Full of N/A: Notes from a V.League Training Session

On the laptop screen in the analysis room of a V.League club, the data table has twenty-eight rows. Nineteen of them read N/A. The distance-covered column is empty. The sprint-count column is empty. The duels-won column is empty. The man at the screen is a twenty-six-year-old analyst who has just finished an online course in probabilistic modelling. He has software, he has a computer, he has a twelve-month contract. What he does not have is data.

That morning's session ran ninety minutes. I stood on the touchline, notebook open, logging every change of direction along the midfield line. The head coach walked past, stopped behind the analyst, looked at the screen for about four seconds and asked exactly one question: "How far did my midfield run?" Nobody answered. The team's GPS vests had lost their sensors in the previous match, and no one on the coaching staff knew until that moment.

That was the moment I understood something no report prints: most of what passes for data analysis in Vietnamese football is running on empty cells, and people still sign it off as if it were full.

A match without crowd noise still tells you more than an entire noisy season. But a data table with no data tells you nothing at all — it only manufactures a false sense of security.

Over the past four seasons, the number of V.League clubs equipping players with GPS vests has risen sharply. Clubs with financial muscle hire analysts, buy video-cutting software and sign contracts with international data providers. Smaller clubs do it differently: an assistant coach doubles as the clip editor, a substitute goalkeeper logs minutes played into an Excel file. The gap between those two groups is not about money. It is about who actually has a person sitting down to watch the footage again.

There is a paradox few people mention. Vietnamese football does not lack raw data. Every matchday produces hundreds of passages of play, thousands of touches, tens of thousands of metres covered. What is missing is a synchronised recording system: not every stadium has enough cameras in the right positions, not every match has someone entering the data immediately after the final whistle. The result is data that exists but cannot be stitched together — like a notebook torn into pieces, each piece sitting in a different department.

I once worked as a data contributor for a football news site. My job was to update live events while matches were running. One night I had to file from a hospital bed, a drip in my arm, a laptop on my thighs, phoning two colleagues far away so that one could check the numbers and the other could verify the sequence of play. The team I was covering won four-nil, and the piece was finished twelve minutes after the final whistle. That night I learned something: in a crisis, what saves the work is not the software, but a clear division of tasks and one person who owns the final call.

At that club, nobody owned the final call. The post-session report went out with nineteen empty cells, and no one on the coaching staff questioned it. Three weeks later the team lost two consecutive matches in the second half, both inside the final twenty minutes. The media blamed the defence.

I asked to rewatch the footage of those two matches. I sat for four hours, noting every turnover in the middle third. A pattern repeated: after the sixty-fifth minute, there was no one covering the space behind the holding midfielder. Not because the midfielders were lazy. Because the two central midfielders were forced to push higher to compensate for a teammate who kept running into the wrong positions. That player was not the weakest in the squad. He was the player who ran the most — literally the most — and that was precisely the problem.

A high distance-covered figure can be a sign of diligence, or a sign of running in the wrong places. Without footage, nobody can tell the two apart. A central midfielder like Nguyễn Hoàng Đức or Đỗ Hùng Dũng creates value in moments no metric captures: receiving the ball with his back to goal, holding the tempo, dragging the whole team ten metres back. That kind of data only exists in the eyes of someone sitting close enough.

It is also why I never write analysis before checking at least three sources and watching the full footage. That habit was formed at seventeen, when I commentated live on a semi-final and got the winning team's approach completely wrong. I said they would press high. They deliberately surrendered possession and counter-attacked. It took me seven days of rewatching every passage to understand where I had gone wrong.

Collapse does not arrive with a single conceded goal. It arrives through hundreds of small details that were ignored. At that club, the ignored details were a broken sensor and a player who spent a whole season running into the wrong positions. Neither showed up in any statistical table.

The dressing room is where the truth outlives any contract. In one season following a Super League side, I watched a young midfielder lose focus after an internal disciplinary sanction, and a goalkeeper hide a shoulder injury for three matchdays. No metric detected either of those things. But when I requested the squad's GPS data from the previous five matches, the weakness showed up in midfield, not in defence as everyone assumed. Data and the dressing room said the same thing — but only because both existed at the same time.

There is a widespread misunderstanding from the outside: that Vietnamese football is weak because it lacks data. After years of following it, I think the opposite is closer to the truth. We have too much unusable data, and a large share of published analysis is produced from spreadsheets the writer has never once cross-checked against footage.

People believe a correct number is an objective number. But a number is only objective when it is placed beside the person who produced it. The same pass-completion figure, in a match where the team dominated the ball and in a match where the team was pinned back, carries two entirely different meanings. Removing the human from the number is the first step towards a wrong conclusion — and the second step is printing it in the newspaper.

At a stadium with no supporters, I hear boots striking the grass more clearly than the referee's whistle. Matches without crowds taught me that football does not need noise to function, but it does need someone watching. A misplaced pass, an unoccupied zone, a silent minute after a mistake — those are the data points that appear in no exported file.

The question I carried home from that training session was not what the club was missing. It was this: if a report can travel straight from a desk into the coaching staff's meeting room without anyone reading it, how many decisions in the V.League are being made on empty cells? Next season, as clubs keep signing analysts and buying more equipment, the question worth asking is not who has the most data, but who has someone responsible for opening every cell and reading it to the end.