Louis van Gaal’s irritation about Manchester United’s “long-ball United” tag manifested itself in an unorthodox press conference on Tuesday in which he armed himself with a four-page pamphlet of statistics aimed at dismantling Sam Allardyce’s allegation and then asked his audience to deliver it to the West Ham manager. “Copy it and go to Big Sam,” the indignant Old Trafford manager said.

Van Gaal’s dossier of A4 sheets shows his team played almost twice as many long balls as West Ham – 83 against 45 – during the 1-1 draw at Upton Park and that 24.2% of their passes were of that manner compared to 22.5% for their opponents. However, the United manager argued Allardyce had unfairly misrepresented the statistics and pointed out 41 of United’s long passes were actually hit sideways rather than to their attackers. In that case, his argument was that West Ham played a considerably higher percentage of long balls forward according to their number of total passes – at 71.1% compared with United’s 49.9%.

The dossier also included diagrams of where every single pass had been aimed – successful ones highlighted in blue, unsuccessful in red – and a separate page for the period after the 76th minute when Marouane Fellaini was brought on. Van Gaal took exception when journalists pressed him on whether he had abandoned United’s traditions to accommodate Fellaini as a target man. “Because of Big Sam, you are talking in behind,” he said.

It was a robust and choreographed response from Van Gaal, though the unusual nature of producing a series of fact-sheets did bring back memories of the infamous press conference when Rafael Benítez produced the “facts” in his Liverpool days concerning Sir Alex Ferguson and refereeing decisions.

Van Gaal’s relationship with Allardyce has not deteriorated to that point but it was clear he was distinctly unimpressed to find a manager renowned for long-ball tactics pointing out that West Ham “couldn’t cope with long-ball United – it was thump it forward and see what you get”.

“When a colleague of mine is saying this kind of thing, you have to see the data and put the data in the right context,” Van Gaal said. “Because I expected this question, I have made an interpretation of the data and I have to say that it is not a good interpretation from Big Sam. It is not so difficult to read. You have to look at the data and then you will see that we did play long balls, but long balls wide, rather than to the strikers.

“We were playing ball-possession and after 70 minutes we did not succeed, in spite of many chances in the second half, so I changed my playing style. Then, of course, with the quality of Fellaini we played more forward balls and scored from that, so I think it was a very good decision of the manager.

“But when you see, overall, the long ball [statistics] West Ham have played 71% of their long balls to the forwards and we [played] 49%. So I will give you this data and you can see that the blue ones are the good ones. Again, they did 71 and we did 49, and I give it you … you can copy it and you can go to Big Sam and he will get a good interpretation.”

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Allardyce may still need some convincing given that earlier in the day he had described it, Benítez-style again, as “a fact and everyone loves facts”. Van Gaal’s team, he said, had been “playing direct football to try and overcome a defeat and it paid off for them”.

The statistics after Sunday’s game showed that in the five major European leagues only Burnley and Metz had played more long balls this season than Van Gaal’s team.

His press officer, Karen Shotbolt, could be seen grimacing on camera when he handed over his dossiers but Van Gaal had clearly planned what to say and it was a terse response when he was asked whether it was going against United’s style to start aiming balls towards Fellaini.

“You start [the question] wrong because Marouane Fellaini was not playing before 70 minutes. We did not do that [hit it long]. I am sorry, you are saying what is not happening. We can play along the floor, and we did against Cambridge [in the FA Cup fourth round], so it is not true what you are saying. Because of Big Sam, you are talking in behind, but it is not like that.”

It was quite a performance, culminating in Van Gaal insisting that he was satisfied with their playing style and defending his decision to use Wayne Rooney in midfield. “I think we have played attractive games and less attractive games, with every club, so there’s no discussion.”

Van Gaal, meanwhile, has denied an FA charge of misconduct following comments made after United’s goalless draw at Cambridge last month and has requested a personal hearing.