Real Madrid drew 4-4 with Real Sociedad at the Santiago Bernabeu to book their place in the Copa Del Rey final for the second time in three seasons.
Goals from Jude Bellingham, Antonio Rudiger, Endrick and Aurelien Tchouameni were enough to conclude the eight-goal thriller, which saw Real Madrid edge the tie 5-4 on aggregate.
It was not the goalscoring that would have become Carlo Ancelotti's biggest worry, though. It would have been Real Madrid's awful defending. Conceding four goals, no matter what the context is, is an awful thing for a club of Real Madrid's stature.
Real Madrid will find out who they face in the final scheduled on April 26, but one thing is for sure: they will have to defend much better.
What makes things worse is that Ancelotti has yet another thing to worry about now.
Real Madrid fielded Raul Asencio and David Alaba as the two central defenders against La Real on Tuesday, and it did not go well.
David Alaba probably had the worst match of his Real Madrid career vs Real Sociedad
Asencio was OK - he was not at his best but nowhere near his worst. The problem was Alaba, who was obviously very unlucky but ultimately had a bad performance that almost cost Real Madrid a trip to Seville.
He scored two unfortunate own goals, and was brutally dominated in the air by Mikel Oyarzabal in Real Sociedad's fourth goal, which just showed that even though Alaba was a brilliant player back in the day, maybe it is finally time for Real Madrid to move on from him.
Alaba has had bad performances in the past, but this was another level. He was alright until the end of the first half, but the second half was just very unlucky for him and he lost his confidence bit by bit.
Ancelotti's worry now would be how less breathing room he has at CB now. Alaba may be trusted in the odd game against Leganes or Espanyol, but any team that poses an aerial and pace threat in the attack will not bode well for Alaba.
Alaba will be better than what he showed on Tuesday, but even before his injury, he was showing signs of decline. It will probably get worse now, which limits Ancelotti's defensive options for the rest of the season.
The Austrian center-back is also among the highest earners in the squad, which also shows another reason why Real Madrid need to move on from him in the summer and get another center-back in.