Madrid - Real Madrid's search for a return to form will be severely tested when the La Liga leaders travel to face an Athletic Bilbao side still high from reaching the Copa del Rey final on Saturday.
Madrid saw their advantage over Barcelona at the top of the table cut to two points after being held 1-1 at home by Villarreal last weekend.
Los Blancos have dropped seven points in their 10 La Liga matches since ending a trophy-laden 2014 on a 22-game winning run.
And with a potentially decisive El Clasico clash with Barcelona now just two weeks away, Madrid can't afford many more slip-ups in their quest for just a second La Liga title in seven seasons.
However, Bilbao is often a treacherous destination for the European champions with last season's 1-1 draw in which Cristiano Ronaldo was sent-off a case in point.
After a difficult campaign, Athletic also come into the game in high spirits having set up a Cup final against Barcelona for the third time in seven years thanks to a 2-0 win at Espanyol on Wednesday.
The Basques have also managed back-to-back league wins against Rayo Vallecano and Eibar to ease any relegation fears.
Madrid will again be without the injured trio of James Rodriguez, Sergio Ramos and Sami Khedira, whilst Luka Modric remains unlikely to feature despite stepping up the intensity of his training after a three month absence due to a thigh muscle problem.
Barcelona have an easier task on paper when they entertain Rayo Vallecano in the Sunday lunchtime kick-off.
The Catalans will be without Sergio Busquets, who suffered a high ankle sprain in the 3-1 win over Villarreal in midweek which sealed a 6-2 aggregate victory in their Cup semi-final, but the club remains hopeful he will be fit to face Madrid and Manchester City later this month.
Luis Suarez extended his scoring streak to five goals in five games in that match as he becomes an increasingly important part of a deadly front three also including Argentina and Brazil captains Lionel Messi and Neymar.
"Every week I try to help the team and I feel better on the pitch all the time," said Suarez.
"For a striker, it always makes you happy to score to help the team no matter what the competition is. The most important thing is to be useful."
The game of the weekend, however, comes at the Vicente Calderon as third faces fourth when Atletico Madrid host Valencia.
A run of four consecutive wins has brought Valencia to within a point of the champions as they edge closer to a return to the Champions League next season.
"The goal is to get into the Champions League; that is paramount. It's what we on the team have in our minds," Valencia striker Paco Alcacer told the club's website.
"Obviously we are playing against the reigning champions, which makes things very difficult.
"What is perfectly clear is that we will try to get what we can from the game. We want to take the three points, but they are the favourites."
Atletico will be without their top scorer in La Liga Antoine Griezmann due to suspension, so Fernando Torres is expected to partner Mario Mandzukic in attack.
However, Diego Simeone's men will be boosted by the return of Spanish international Koke to the starting line-up after he made his comeback as a substitute from a hamstring injury last weekend in a 0-0 draw at Sevilla.
Levante v Eibar
Deportivo la Coruna v Sevilla , Athletic Bilbao v Real Madrid , Elche v Almeria, Granada v Malaga
Barcelona v Rayo Vallecano , Real Sociedad v Espanyol , Villarreal v Celta Vigo, Atletico Madrid v Valencia
Cordoba v Getafe