Zinedine Zidane has passed every test asked of him in his short coaching career so far. Real Madrid is on top in La Liga and on course for just a second title in the last eight years.
Last month his side beat Atletico Madrid 3-0, away from home.
Barcelona dominated the next half hour, and had three good chances to double the lead and kill off the game.
Neymar, Andres Iniesta and Lionel Messi all missed opportunities to make it 2-0.
Here are three thoughts on the match and its fallout: It may be only 14 games into the season, but this clash had a season-defining element to it.