I wouldn't say Real Madrid performance is that so bad, even though they haven't won consistently the players have tried their best. They had a great competition with Barcelona in the Copa del Rey and were very close to winning. In fact luck has not been in their favor and recently Ancelotti may be lagging behind the opponent's strategy. From this, Barca are going through their best time and are in a great position to win the trophy and then wait to win the La Liga trophy. I think Real Madrid is a big obstacle in front of them now. Real Madrid are second in the point table will use all their strength to win at least this trophy this season. I think they will return to their best game and will be able to beat Barcelona.
There's no doubt that Real Madrid have performed nicely this season but it's just that they encountered lots of issues beyond their control along the way which caused them to decline a bit, they had too many injury problems with important players like Carvajhal, Militao, Alaba. Barcelona on the other hand didn't experience much injuries and have been fortunate enough to always take their chances all through the season and trying always to move on whenever they make a mistake, I believe this has been one of the secrets behind the team's success story this season that have helped them in being so consistent all the way.
It is very unfortunate that Real Madrid has so many injuries. Because the main reason why they have not played well in many tournaments this year is injured players. Because most of the injured players are good players in the defense area. Real Madrid has had great difficulties because there were no quality players to replace them. They were eliminated in the Champions League and had to accept Barcelona's superiority in the league. This year is an unfortunate season for them.