Atletico Madrid and Real Madrid kick off their respective matches on Sunday knowing anything other than a win is not enough if they are to maintain their challenge for the Spanish Primera Liga title against FC Barcelona.
Atletico coach Diego Simeone has some difficult choices to make as his side also faces a midweek trip to face PSV Eindhoven in the Champions League on Wednesday, just three days before the Madrid derby the following Saturday.
With Villarreal in fourth place, he cannot afford to rest key players, but tiredness could become a factor over the following week if he doesn't.
Simeone will also keep an eye on the top scorer, Antoine Griezmann, who would miss next weekend's trip to the Bernabeu if he picks up another booking on Sunday.
Real Madrid will travel to the south of Spain with their morale high after their Champions League win and with the knowledge that they will then have a full week to prepare for the derby.
Gareth Bale is still out with his calf injury and Zinedine Zidane will have to make choices in defence due to the foot injury suffered by Pepe and a suspension for Rafael Varane, who was unlucky to be sent off for two yellow cards last weekend against Athletic Club.
His absence means Nacho Fernandez will get a rare start alongside Sergio Ramos in central defence while Dani Carvajal and Marcelo are the full backs.
Isco is likely to return to the starting 11 and will face an emotional return to the club which sold him to Real Madrid, but with an important gap to close at the top of the table and a crunch match the following weekend, there will be no room for sentimentality.
