Madrid - Almost exactly an hour after the final whistle, Barcelona posted a tweet: "Congratulations to @realmadrid for winning the 2017/18 Champions League title."
Underneath some fans demanded the message be deleted immediately while others claimed it as a classy touch. "We are rivals, not enemies", one wrote.
Meanwhile, Barcelona's key players - Lionel Messi, Gerard Pique, Luis Suarez, Andres Iniesta - stayed quiet. Some had recently posted pictures of themselves surrounded by their families, with the World Cup just around the corner.
But from the words that have been spoken since, and despite the club's stately message, it is clear Madrid's triumph hit home. Barcelona had failed and this made it even harder to bear.
"Obviously it's infuriating (for us)," Suarez said in an interview with RAC1 earlier this month. "Madrid have won the Champions League in each of the last three years. They have made history and it's a thorn in our side."
Chiefly, perhaps, because Barca will feel they were better than Madrid last season.
They blew them away in a 3-0 flurry at the Santiago Bernabeu and then played with 10 men for the second half at the Camp Nou and still drew 2-2. They even led with a man fewer until Gareth Bale's late equaliser.
They also finished an enormous 17 points clear of them to win La Liga, a gap that admittedly swelled when Zinedine Zidane began prioritising games in Europe, but even by February, before the Champions League knock-outs kicked into gear, Barcelona were 16 ahead.
A pattern has emerged in recent years that both clubs are keen to break. Barcelona dominate domestically, while Real Madrid reign in Europe.
Barca have won seven out of the last 10 league titles, Madrid only two. Real have claimed four of the last five Champions League crowns, Barcelona the other one.
But while Madrid's victory over Liverpool was a final blow, it was the defeat to Roma, and the manner of it, that was the moment of realisation.
Throwing away a 4-1 lead by losing 3-0 in Italy was not perceived as just careless, it was unforgivable.
"Without personality, without Messi and without any fight, Barca were shipwrecked at the Olimpico against an immensely superior team that lowered the Barca players from their artificial pedestal," read Madrid's daily newspaper AS the following morning.
"We have to endure the pain," said coach Ernesto Valverde. "There will be some tough days."
His team were stinging for the rest of the season, even as they completed the double by thrashing Sevilla to win the Copa del Rey.
Before the match, reports had surfaced that Valverde could be sacked regardless of the result. After, the players were asked if victory made up for their Champions League exit. The prevailing answer was no.
"It is an important trophy," Suarez said. "But this does not hide what happened in Rome."
Motivation is one thing but shifting weight onto the Champions League will demand practical adjustments too.
Valverde was accused last season of over-exerting his players in the league, particularly when it was clear it was won.
Three days before the capitulation to Roma, the likes of Messi and Suarez were playing 90 minutes to beat 14th-placed Leganes.
Valverde has indicated he will adapt. Ahead of their Group B opener at home to PSV on Tuesday, Sergio Busquets and Philippe Coutinho started as substitutes in Saturday's win over Real Sociedad, even if both were needed before the end.
Messi, who turned 31 in June, may also need to be preserved if he is to add a fifth Champions League success to his collection. Now captain, he appears hungrier than ever.
"It's time to win the Champions League," Messi told Catalunya Radio earlier this month. "We've been knocked out in the quarter-finals three seasons in a row and maybe the last one was the worst of all because of the result and how the match was played.
"I think we have to aim for that, as a club, as a team and as a collective. We have a spectacular squad and we can do it."