This was always going to be a tough opening test for a Tottenham side full of new partnerships and lacking attacking threat but the manner of the defeat would still have disturbed Roberto De Zerbi.
Spurs did not look ready in the slightest for the start of the Premier League season and the pace and intensity that Brentford hit them with from the off caught them off guard like a staggering boxer.
So poor were the visiting team that the home fans began singing at their opponents in the second half: "Thomas Frank, he's laughing at you."
In all, Brentford sent 26 shots at Tottenham's goal while De Zerbi's blunt collection of players managed just nine, with only four of them on target.
If there is a team you must commit 100 per cent to duels against, it's Brentford. It's like walking around the land of the giants at their home with set pieces pinged constantly to the heads of Kristoffer Ajer or Nathan Collins. If you let them, they will physically dominate you.
In truth this Tottenham side may never start together as an XI again and they looked like they had met for the first time on the morning of the match.
Mikey Moore will likely head out on loan to Koln in the coming days, Mateus Fernandes showed why he won't be left out of the starting line-up again, Pedro Porro will return at right-back as will Micky van de Ven in the centre.
The entire front four will likely be different in seven days' time against Newcastle with Savinho and Omar Marmoush to join and James Maddison, Dominic Solanke and the returning Mohammed Kudus, who was at the match, all set to push their claims.
Bees boss Keith Andrews understood where this Spurs side is at: "I promise you that it'll be a different game when we face them next time."
FOLLOW OUR TOTTENHAM FB PAGE! Latest Spurs news, analysis and much more via our dedicated Facebook page
That won't take away the sting of this flat, uninspiring derby display though for De Zerbi or the dejected 1,725 travelling fans, as Brentford beat Tottenham for the first time at the Gtech Community Stadium.
Among those in attendance was rock star Jon Bon Jovi but it was Spurs who were living on a prayer for most of the game as Brentford peppered their goal with shots.
It was Spurs' joint-heaviest defeat on their opening day of a Premier League season, with a 3-0 defeat to Manchester United back in 2011.
It bore too many hallmarks of last season's dismal displays and the biggest problem for De Zerbi is that there were only the most fleeting glimpses of his football that should have been drilled deeper into them this summer. Only a couple of one-touch first half moves hinted at what is to come.
As with United's loss at Hull earlier in the day, while plenty of credit must go to the home side, Spurs looked like they were still in pre-season mode and the need for attacking additions was glaring.
When football.london asked De Zerbi what went wrong, he launched into a lengthy monologue with a long list of issues.
"For many reasons I think we are not a team yet. Yesterday in the press conference, when you asked me what is the target, we can fix the target when you become a team. Before becoming a team, we can't say what we can do," he said.
"We are not in the right point in physical condition for a lot of reasons. The players, they came late after the World Cup, because in Australia we couldn't work in the right way for the trip, didn't take risks for a lot of things, but these are not excuses.
"They are the normal situation when you are building a new project, a new process. I don't want time, but we have to pass through these problems. I couldn't lose confidence in my players. I believe in my players, I believe in my club, I believe in myself.
"I think we are working well, but in this moment, I knew after the Hoffenheim game, I said we are not in the right point, we are late for the start of the Premier League. But it's a step, we have to improve quickly."
He added: "Anyway, we could fight stronger than we did today. We lost too many duels, we made too many mistakes in the timing when we wanted to push the pressure higher. We arrived second for the second ball, we didn't win one second ball, one duel, one tackle, and it's tough. But if you analyse everything, you can find that we played with one [born in] 2007, one 2006.
"Lucas Bergvall, the second goal. I think he didn't play bad today, even if I substituted him at half-time. But Lucas Bergvall in the next two years, he will not lose that ball in that moment of the game. But there are steps to become better.
"Now the focus and the target is to become a team. Because a team, you can't become a team through the transfer market window.
"You become teams with the players, they find the connection between them, they find the spirit, they find the soul and it's a process."
De Zerbi did not hold back in handing out some tough truths for the younger players while also making it clear that it's all part of their journey.
He said that "we made a lot of mistakes in the timing of the pressure with Mikey Moore. We arrived too many times late and lost too many duels to compete with Brentford."
Moore barely touched the ball in the first half but had three big opportunities in the second period that could have altered the momentum of the game. The first two he sent meekly at Caoimhín Kelleher and the third the former Liverpool goalkeeper saved well.
Just 19, Moore's movement for all three opportunities was excellent, particularly getting on the end of Andy Robertson's dangerous ball for the third but his rushed finishing betrayed his tender years.
De Zerbi admitted that he probably should not have started Bergvall, who he said was 100 per cent staying at Spurs this season, but really had to.
"Bergvall, why not Bentancur? Because he came late in the pre-season. In the pre-season we worked with Lucas Bergvall," said the Italian.
"I think at the beginning of the season, at the beginning of the new project, it was good, it was right to play with Lucas Bergvall. But I knew before the game, Lucas Bergvall, in this type of game, maybe he could suffer more than Rodrigo Bentancur, nine years older, and Lucas, 20. I knew before the game, but at the end you have to think.
"We try to build something good for the club. We need also Archie Gray, we need also Lucas Bergvall, or we work for today. And tomorrow, I don't know.
"For today, I agree. For the plan, for the project, what the club wants and what we are, in the direction we are working, I think is the normal process."
Gray became Tottenham's youngest ever captain in a competitive match, aged 20 years and 163 days - beating Steve Perryman’s record of 20 years and 260 days.
The young midfielder looks set for a season spent as Pedro Porro's back-up for the options in the centre of the pitch are just too plentiful now for De Zerbi.
Gray struggled in a backline that offered him little help or guidance despite his older team-mates. That's because Jan Paul van Hecke, Marcos Senesi and Andy Robertson were all playing their first ever competitive game together and it showed.
"If you analyse last season, the defensive line, Porro, Danso, Micky Van de Ven and Udogie. And today, Archie Gray, JP Van Hecke, Senesi and Robertson, four new players," said De Zerbi.
On Gray he added: "I think he's much better than his performance today. But not just Archie Gray, also JP Van Hecke, Sandro Tonali, Richarlison, everyone. We didn't play a good game.
"But we can't change our idea on Archie Gray because of today, or for Richarlison or Mathys Tel."
Van Hecke and Senesi will need time together. Van Hecke and Van de Ven less so as they played together many times as a centre-back partnership for the Dutch U21s back in the day.
Brentford's first goal saw the defence part like a pair of curtains. Bergvall was passed around with ease before the excellent Mamadou Sangare picked out Keane Lewis-Potter in even more space to side-foot home.
The second goal was equally avoidable. Weak hold-up play from Richarlison, followed by Bergvall's poor decision to try to dribble through when there was no space to do so, gifted the ball to Mathias Jensen. While Antonin Kinsky palmed out his shot, it bounced straight to Vitaly Janelt to tap home.
The third goal came within four minutes of the second half as Kinsky saved Sangare's low strike through a crowd of bodies but the loose ball again fell to a Brentford player as Michael Kayode got in front of Richarlison to knock it into the roof of the net.
It could have been worse when the hosts were handed a penalty soon after when Bentancur brought down Kevin Schade in the box. However, Igor Thiago struck the left-hand post with his spot kick and the ball ricocheted to safety.
Robertson was the only Spurs defender to emerge with anything resembling credit from the game, making some important interceptions and contributing at the other end of the pitch with some dangerous balls into the box.
Senesi did grow into the game and ended up recording more defensive contributions than anyone else on it the pitch with five tackles, six clearances, two interceptions, two blocks and two ball recoveries. Robertson was the second highest Spurs player with 11 defensive contributions.
In front of the defence, Sandro Tonali looked unsure how to play alongside Bergvall, despite their pre-season forays together, and it was only with the half-time introduction of Fernandes and Bentancur that the £100million Italian appeared more assured of his role.
Spurs need Bentancur's aggression to help them control games, while Fernandes showed plenty of moments of quality that will make the 22-year-old a must-pick in the midfield.
It all left the day feeling very experimental, like another pre-season match rather than the opening game of the Premier League campaign.
Spurs will get mocked for this result by rival fans and pundits because of the £237million spent so far, which will rise to around £377million when Savinho and Marmoush arrive. In truth though, this barely resembled the team De Zerbi is trying to build. It was a Frankenstein's monster of bits and pieces of his squad while he awaits the final parts to arrive and others to return to full fitness.
A Spurs team able to call upon Savinho and Marmoush along with a fully fit and sharp Kudus, Maddison and Solanke, with Kulusevski, Xavi and Odobert to return as the season progresses, will create and score goals aplenty. There's also potentially Cody Gakpo, depending on what Liverpool do in the final days of the transfer window.
Spare a thought for 17-year-old Luca Williams-Barnett who thought he was getting called upon to make his Premier League debut late on in Saturday's defeat, only to realise after beginning to run back from his warm-up amid his excitement that the Spurs staff member was actually pointing behind him and telling him to get Destiny Udogie to come back instead.
For the sake of the four remaining minutes of normal time, De Zerbi could have handed the teenager his big moment rather than give his Italian left-back the briefest of run-outs.
Hopefully the talented Williams-Barnett will get his chance in front of the fans at the Tottenham Hotspur Stadium during Wednesday night's Carabao Cup match against Charlton, who beat West Ham in the Championship on Saturday.
The match will give De Zerbi the chance to get more of his squad sharper, particularly Maddison, who looked like a player that hasn't started a competitive match in 16 months albeit he still got the ball into the Brentford box unlike Conor Gallagher, and Solanke who was way off the pace.
De Zerbi will continue to tinker with his team and tweak it until it's right. That's what the Italian does.
Even subconsciously during press conferences the 47-year-old is constantly touching things on the table in front of him, organising the table cloth or the microphone.
In Friday's pre-match press conference, when the reporters went to pick up their phones that had recorded De Zerbi's words off the desk, they found they had all been lined up perfectly in a defensive wall of sorts by the Spurs boss.
It's one thing to get a line of phones in order, now he must get Tottenham Hotspur in order and that's a challenge that has defeated many before him.
The transfers of Savinho and Marmoush can at least deliver a transfer pick-me-up for everyone involved but as De Zerbi said, it's not about the names, it's about becoming a team and time waits for no one in the Premier League.
