The match saw Cristiano Ronaldo throw a tantrum toward the end of the game, in reaction to Gareth Bale's failed free-kick at the death.
The moment was captured by Twitter account Messi Left Foot:
Ronaldo's dissent was clear to see after Bale's failure, but Galacticos manager Carlo Ancelotti moved swiftly to play down the incident and support his team's fading hopes.
The Italian coach said, via the club's website:
Cristiano Ronaldo was annoyed because we were losing the match, nothing more. Now La Liga is more complicated because we are behind. It's more complicated but not impossible.
It's not a problem. The team has lost against smaller teams. La Liga is complicated and it has strong teams and every match is difficult. We have to think about ourselves. We lost two matches but we have to believe we can win it. We are behind but we have to believe it is possible.
Madrid defender Marcelo also offered his take after the game. The club's website quoted the experienced Brazilian campaigner saying: "Of course we players suffer psychologically but we cannot stop working hard and we are going to keep doing so to get Real Madrid to where it should be. It is difficult to win several matches in a row like we have."
Ronaldo's reaction is not surprising as Madrid's collapse only highlights Barcelona and Lionel Messi's rise to form in the final part of the season.
Pete Jenson of The Mail Online also reported that record-signing Bale was off the pitch changing his boots during the scoring of Sevilla's winning goal, compounding the misery on the night for the Welshman and his Portuguese superstar team-mate.
As the finishing line comes into view, Madrid now need to stick together and rescue their form as soon as they can. One more defeat will likely see their title challenge vanish and their dreams of adding another La Liga crown over.
Ronaldo and Bale have been sensational in recent months as a wide-attacking pairing and before the Clasico looked like they could run away with the titles both at home and in Europe. But this incident and result shows how delicate the Galacticos ecosystem is.
Ego drives these players and when things start to go wrong their levels of resilience fail. Bale represents the future of Madrid and is well aware that Ronaldo is still the alpha male right now.
But that power shift will start to creep in as Bale settles at the club and tries to reinforce his own position as the costliest Galactico in history.
This could ultimately damage Madrid's morale at vital times in future campaigns, as it seems to be now. This will only allow Barcelona an increased opportunity of staying one foot ahead of them in the next few seasons.
Madrid's superstars need to beat their own personal ambitions first before they can win the biggest trophies in football as a team.