Real Madrid were held scoreless in a LaLiga away game for the first time under Zinedine Zidane as their attacking concerns resurfaced in Saturday's 0-0 draw with city rivals Atletico Madrid.
The visitors struggled to create chances in battling to a second blank of the season and first on the road in 35 top-flight matches.
Zidane will be particularly concerned by the form of Karim Benzema and Cristiano Ronaldo, the pair having now scored just twice between them from a combined 16 league appearances this term.
In addition to leaving the champions 10 points shy of Barcelona – a gap never previously overcome by any team in a LaLiga title race - the stalemate means Los Blancos have scored 11 fewer goals than Ernesto Valverde's men over the opening 12 fixtures.
