Analysis: Four things we learned in Spain's Matchday 4

The fourth round of games in La Liga saw Real Madrid continue its excellent start to the season, while Barcelona smashed Valencia and Atletico Madrid showed signs of life. Here are some things we learned in Spain this weekend.

1 Mbappe makes the difference as Real Madrid win with 10 men

Kylian Mbappe continued his fine start to the season as Real Madrid won 2-1 at Real Sociedad.

Mbappe took advantage of a dreadful back-pass that put him through on goal to give his side an early lead and even though Madrid was reduced to 10 men with Dean Huijsen's red card, the Frenchman produced a special piece of skill to get past his marker and give Arda Guler a simple finish to double the lead.

Xabi Alonso's side then showed the discipline needed to hold Real Sociedad at bay, even though Mikel Oyarzabal's penalty gave the home team hope of a fightback.

2 Barcelona cruise past Valencia

Forced to host Valencia at the 6,000-seat Johan Cruyff Stadium amid massive debts and ongoing Camp Nou renovations, Barcelona underlined their off-field turmoil, but a 6-0 home win showed how well Hansi Flick's side plays on it.

Flick was without Frenkie de Jong and Lamine Yamal, but the duo were hardly missed as Marc Casado and Ferran Lopez - both nearly sold in the summer - impressed, and Robert Levandowski scored twice to underline his status as a complete striker.

Flick will be especially happy with the display because Yamal will likely need some rest this season if the teenager is to avoid further injury problems.

3 Atletico impresses against solid rival

Atletico Madrid went into Saturday's match at home to Villarreal with the pressure on coach Diego Simeone after taking just two points from the start of the season.

With Real Madrid winning, anything but a win would have left Atletico at least nine points behind its local rival, but Simeone's side responded with its best display of the campaign.

The attack and midfield pressed high up the pitch to prevent Villarreal's rapid forwards from getting into the game, and the win shows what Simeone is looking for in the campaign.

The bad news came with injuries to defenders David Hanko and Robin Le Normand just ahead of a run of six games in three weeks.

4 International break a problem for coaches

The return to action after the international break also showed the problems that players leaving to play for their countries can cause.

Atletico lost Hanko and Le Normand through injury after they played for their countries, while Lamine Yamal was unavailable for Barcelona through injury, with Hansi Flick pointing the finger at Spain coach Luis de la Fuente for playing the winger when not fully fit.

Meanwhile, Athletic Bilbao lost Nico Williams to a groin injury, and after his electric start to the campaign he was clearly missed, while elder brother Inaki was also below par after playing for Ghana during the break.