Atletico Madrid and Real Madrid have concerns over the fitness of key players ahead of the first meeting between two sides from the same city in the European Champions League final in Lisbon tomorrow.
Real are worst affected as defender Pepe and striker Karim Benzema remain major doubts, but coach Carlo Ancelotti has insisted that World Player of the Year Cristiano Ronaldo will start despite a muscle problem which has prevented him taking a full part in training.
Atletico are almost certain to be missing their top scorer Diego Costa despite the Brazilian-born striker reportedly travelling to Serbia to receive special horse placenta treatment on a hamstring injury this week.
Ronaldo pulled out of Real's final La Liga game of the season against Espanyol last weekend because of an ongoing hamstring injury, which also caused him to miss crucial games in the Liga title run in as Real lost out to champions Atletico.
However, the Portuguese forward will return to the city where he started his playing career with Sporting Lisbon and admitted he is desperate to finally lead Real to their 10th European Cup after five seasons with the club.
"It will be a special game. I will be playing in my home country, in Portugal," the 29-year-old said.
"It is my first final with Real Madrid, so that will be special too and it will be against a great team in Atletico.
"They have had an amazing year, but we are going to give our best and try to win because we want that 10th title."
Real defender Sergio Ramos has claimed that Atletico's title triumph makes them the favourites to lift the trophy for the first time despite having a budget less than a quarter of their more illustrious city rivals.
Atletico could seal the greatest season in their 111-year history should they manage to beat Real in just their second appearance in the final.
Most of the credit for Los Rojiblancos' amazing success in recent seasons has gone to manager Diego Simeone, but the Argentine has hailed the effort shown by his players to overcome the financial disadvantages Atletico have in relation to Europe's biggest clubs.
"This season has been the fruit of the labour that we've been doing for nearly three years," he said.
"From the strikers right through to the goalkeeper, the team is aware of how we need to play in order to succeed, in order to highlight our strengths and hide our weaknesses because, although we do have weaknesses, we just hope not to show them."
A reported 200,000 fans turned out to celebrate Atletico's title triumph in the centre of Madrid last weekend with even more expected to party should they return across the Portuguese border having won the Champions League.
And Simeone thinks the club's fans can associate with the spirit embodied by his side.
"It is great that in one city you have such a powerful team as Real Madrid and a battling team such as Atletico Madrid. The idiosyncrasies of the clubs couldn't be more different, possibly from a social perspective as well. Each team uses the tools it has at its disposal and it's a great rivalry, no matter which team you support."
Atletico also have concerns over the fitness of playmaker Arda Turan after he was forced off with a hip injury in the 1-1 draw away to Barcelona that sealed the domestic league title, but the Turkish international is expected to feature at some point even if not fit enough to start.