Forward Diego Lopez put Valencia ahead on 33 minutes -- his first goal for the club, on his second start -- slotting past Madrid goalkeeper Thibaut Courtois after an intricate team move.
Madrid looked to respond in the second half, with substitutes Federico Valverde and Toni Kroos both denied by spectacular saves by goalkeeper Giorgi Mamardashvili, and Vinicius Junior was sent off in added time after clashing with Valencia's Hugo Duro.
1. Racist abuse aimed at Vinicius spoils already-tense game
The postmatch discussion of this game, which had already been incident-packed, will be dominated by what happened in the second half at Mestalla. Play stopped for almost 10 minutes as an initially bizarre sequence of events took on a far uglier tone, with Vinicius Junior alleging that he had been racially abused by a fan.
It began with Vinicius on the ball, dribbling down Real Madrid's left side, when a second ball was thrown onto the pitch from the crowd. Valencia defender Eray Comert went to kick that ball off, and -- whether intentionally or not -- did so straight at Vinicius, striking the other ball at the forward's feet. The result was a yellow card for Comert and a free kick for Madrid, but it didn't end there.
As Madrid prepared to take the set piece, Vinicius began pointing animatedly at a fan in the crowd behind the goal. It was obvious that something had been said. After long discussions with teammates and referee Ricardo De Burgos Bengoetxea, who asked if Vinicius wanted play to be suspended, the game continued, with the crowd being warned over the stadium megaphone about racist abuse.
Later, in time added on, a mass brawl in the Valencia box ended with Vinicius being sent off after striking Valencia's Hugo Duro. There was then a further confrontation with the Valencia bench on Vinicius' way off the pitch.
All that will take some unpacking, but the bottom line is this: Vinicius has repeatedly suffered disgusting racist abuse from fans this season. LaLiga have vowed that they are doing what they can to identify and punish those responsible, and they must do the same again today.
2. Madrid slump continues despite much-changed XI
Coach Carlo Ancelotti was looking for a response from his players after their Champions League thrashing by Manchester City in midweek. He didn't get one. Ancelotti made six changes to his starting XI, with Ferland Mendy, Antonio Rudiger, Lucas Vazquez, Aurelien Tchouameni, Dani Ceballos and Marco Asensio coming into the team and Dani Carvajal, David Alaba, Kroos, Luka Modric, Valverde and Rodrygo Goes all benched.
That attempt to inject some energy into the team didn't work, though. Instead it was Valencia who showed an intensity and hunger inspired by their desire to avoid relegation. One team was fighting for its life here; the other, with only finishing second above rivals Atletico Madrid to play for, would prefer the season to end already.
There was plenty on the line for some of these Madrid players individually. Tchouameni needs to find the early season form that had him looking like a ready-made replacement for Casemiro. Mendy would like to quieten the doubters who say he lacks the quality -- and the fitness levels -- to be a fixture in a Real Madrid team. Ceballos and Asensio should be seizing on opportunities like this to prove they deserve to be a part of Madrid's future.
None of them succeeded -- Tchouameni performing best -- and those questions remain unanswered.
3. Valencia kids lead charge to beat the drop
Valencia, one of Spain's most successful, historic clubs, have been at serious risk of being relegated for just the second time in their history this season. This win is a huge step towards safety, taking them up to 13th in the table, on 40 points. It was fitting, too, that it came on their iconic Mestalla stadium's 100th birthday.
Valencia's revival in recent weeks, after they looked to be on an irreversible downward spiral, has been remarkable. They've now picked up 13 points from a possible 18 in their past six games, including crucial wins against struggling Elche, Real Valladolid and Celta Vigo, and now Madrid.
That their recovery has been led by academy players has made it even more special. Midfielder Javi Guerra, 20, scored the winner against Valladolid; Alberto Mari, 21, did the same against Celta; and now wide forward Diego Lopez, 21, gave them all three points against Madrid.
The appointment of club legend Ruben Baraja as coach looked like a costly mistake when he first took over in February, but giving the kids the keys to this team -- and getting the fans onside -- has made the difference.
Best and worst performers
Best: Giorgi Mamardashvili, Valencia
The goalkeeper made incredible second-half saves from Valverde and Kroos.
Best: Diego Lopez, Valencia
He scored a priceless goal that could keep his team in the first division.
Best: Thibaut Courtois, Real Madrid
The goalkeeper was Madrid's best player on the night, keeping the score at 1-0.
Worst: Ferland Mendy, Real Madrid
Unconvincing on his return to the team.
Worst: Karim Benzema, Real Madrid
Another quiet game, with little goal threat.
Worst: Eduardo Camavinga, Real Madrid
Played only the first half before being withdrawn.
Highlights and notable moments
Diego Lopez slides in to score Valencia's opener against Real Madrid.
Vini Jr. picks up his first career straight red card 🔴 pic.twitter.com/sD8kKQX9g8— ESPN FC (@ESPNFC) May 21, 2023
After the match: What the managers and players said
Real Madrid manager Carlo Ancelotti asked for his thoughts on the game: "Do you want to talk about football? I don't want to talk about football. I want to talk about what happened here. I think it's more important than a defeat. ... What happened here today shouldn't happen. That's obvious. That a stadium shouts [a racial slur] at a player and a coach thinks about taking a player off because of that, there's something bad happening in this league."
Key stats (provided by ESPN Stats & Information)
Real Madrid now have four straight road losses in all competitions, longest such streak since September-October 2018 (also four).
Real Madrid have failed to score in three straight road games for the first time since February 2022 (also three).
With his goal for Valencia, 21-year-old Diego López scores his first career senior goal.
Vinícius Jr.: Second career red card (his first came for Real Madrid's B team in October 2018 for two yellows)
Valencia: Los Che visit Mallorca in LaLiga on Thursday (watch live on ESPN+ at 1:30 p.m. ET)
Real Madrid: Los Blancos host Rayo Vallecano on Wednesday in LaLiga (watch live at 1:30 p.m. ET).