MADRID, Sept. 3 (Xinhua) -- Real Madrid kicks off the fourth round of La Liga when Jose Mourinho's side travels to face Real Betis on Friday night.

The game at what is expected to be a hot Estadio de la Cartuja promises to be Real Madrid's sternest test yet after a bright start to the season, with 10 goals in three matches and Kylian Mbappe and Jude Bellingham both in excellent form.

Betis began the season with back-to-back 1-0 wins but suffered a 5-2 defeat at Levante last weekend and will be keen to respond. The Seville club completed the deadline-day signing of Dani Ceballos after he rescinded his Real Madrid contract, but the 30-year-old lacks the fitness to feature on Friday.

Saturday opens with Athletic Bilbao hosting Atletico Madrid at San Mames. Athletic impressed in last weekend's 2-0 win at Celta Vigo as the players continue to adapt to new coach Edin Terzic's tactics, although Terzic may adjust his high defensive line against an Atletico side built to attack on the break through players such as Ademola Lookman and Giuliano Simeone. Much will depend on whether Julian Alvarez features after the transfer window closed without his departure.

Rayo Vallecano continues its nomadic start to the season while work continues at its Vallecas Stadium. Rayo faces Racing Santander in Leganes, with Racing boosted by last weekend's entertaining 3-2 win over Elche.

Villarreal coach Inigo Perez will hope his side's first home game of the campaign also brings its first win after opening the season with two draws and a surprise defeat to Alaves.

Villarreal hosts Deportivo La Coruna, which could hand debuts to new arrivals Jose Gimenez and Marc Casado, who joined from Atletico Madrid and FC Barcelona respectively.

FC Barcelona travels to Valencia on Sunday. Valencia has struggled with one draw and two defeats, and coach Carlos Corberan will hope deadline-day signing Harvey Elliott from Liverpool strengthens the midfield. Reigning champion Barcelona has scored 12 goals in three games, with new arrival Anthony Gordon settling in well.

Alaves faces Osasuna in a tight encounter between two defensively sound sides, while Malaga hosts confident Levante at La Rosaleda. Espanyol needs a lift at home to Sevilla, whose perfect start was ended by Atletico.

Monday's fixtures see Getafe host a Celta Vigo side that has looked fragile at the back, while Elche must address its defensive problems and the sale of David Affengruber as it visits a Real Sociedad side dangerous on the counterattack.