Tottenham are set to submit a formal complaint about the decision not to send off Jayden Bogle for his challenge on Mathys Tel during the defeat by Leeds.
Bogle, 26, escaped any punishment despite catching Spurs forward Tel on the back of the ankle with his studs in the first half of Saturday's game.
It is understood Tottenham believe Bogle should have been sent off and will write to refereeing body Pro Ref to seek an explanation as to why the incident did not result in a dismissal.
The challenge was reviewed thoroughly by the Video Assistant Referee (VAR), but referee John Brooks was not sent to the pitch-side monitor, meaning Bogle escaped any punishment.
Former Premier League assistant referee Darren Cann said the Leeds defender was "fortunate" not to be dismissed.
"Bogle's challenge meets the criteria for serious foul play as he endangers the safety of an opponent," Cann told BBC Sport. "He can consider himself lucky to still be on the pitch."
Roberto de Zerbi's side never appeared to recover from the incident and, after the break, were outworked and outplayed by the home side.
Nevertheless, the Italian - perhaps buoyed by his side's recent rise up the table - refused to pinpoint Spurs' failings on the referee's decision.
"We deserved to lose the game in the second half and didn't play like we can," he told TNT Sports. "It's a journey for us because we can learn from this game.
"I am sorry for the performance in the second half - we didn't play like a top team. We didn't have the right character and physicality in the second half."
When the PA system at Elland Road confirmed there was a VAR check in progress, it seemed only a matter of time before Bogle would be shown a red card.
The Leeds defender was full-blooded in his pursuit of the ball from Tel and seemed certain to follow in the footsteps of Crystal Palace forward Jean-Philippe Mateta, who was sent off for a similar challenge against Spurs last weekend.
What was strange about the situation, though, was that at no point did Brooks make his way to the pitchside monitor to review the incident.
It meant the entire four-minute review was conducted solely by those in the VAR hub at Stockley Park.
"They've said no red card, and this will create debate," former Tottenham midfielder Michael Brown told BBC Radio 5 Live.
And because Brooks had not initially cautioned Bogle, the defender escaped the incident without any punishment.
"I have big confidence in the referee. Nothing changes if he goes to the monitor," said De Zerbi. "If they didn't take the right decision I don't know. We have to keep the eyes on the performance where can improve."
Early in the second half, Tottenham's frustration - seemingly stemming from the decision not to dismiss Bogle - came to a head when defender Pedro Porro and De Zerbi himself were booked simultaneously following a challenge by the Spanish defender.
De Zerbi described the decision to caution Porro as "incredible" after what had transpired during the first half.
"I was surprised on the yellow card for Pedro Porro because it was clear," the Italian told BBC Match of the Day. "The potential red card, I couldn't say.
"We have full confidence in the referee and VAR. I cannot say nothing more."
Bogle was certainly very lucky to escape even a booking.
The foul happened in strange circumstances. Bogle was positioning his body to challenge Tel with his right foot, and in trying to plant his left foot he stood on the ankle of the Spurs player.
At full speed it looked innocuous, which is probably why referee Brooks chose not to show a card after giving the foul.
Once the slow-motion replays were looked at it became apparent that the nature of the contact on Tel was very ugly, with the twist of the ankle.
It could easily have resulted in the VAR, Tony Harrington, sending Brooks to the pitchside monitor for an on-field review for a red card.
Harrington spent far too long looking at the replays, probably feeling he had more time while Tel received treatment. But longer reviews only tend to cause doubts about process.
Harrington eventually told Brooks: "I'm confirming the on-field decision of no red card. There's a lack of speed going into the challenge and he's stepping into the tackle. Confirming a reckless challenge."
A reckless challenge is a yellow card, but the VAR is unable to intervene and advise that Bogle should be booked.
Something else Harrington said is important - "stepping into the challenge".
It does not mean a player cannot be sent off, but this is far less likely to result in a VAR review for a red card because such challenges naturally come with less force.
How about comparisons with Mateta's VAR red card against Spurs last week?
There is an argument that Mateta, who was booked on-field, made less forceful contact on the ankle of Micky van de Ven. Yet it is the nature of the challenge that is crucially different.
Mateta made a lunging, stretching tackle with studs leading, the kind generally considered to come with a higher degree of force and potential danger to the opponent.
That said, and even though Bogle was not really making a challenge, the nature of the contact means many may feel there should have been a VAR review for a red card.
