Real Madrid are currently one point clear at the top of the La Liga table.
However, recent setbacks have dampened the mood around the Santiago Bernabeu.
A 2-1 defeat to Sevilla on January 15 saw their 40-game unbeaten run come to an end.
And their hopes of winning the treble this season have been killed after a Copa del Rey exit to Celta Vigo on Wednesday.
Isco has been linked with moves to Real Madrid and Barcelona
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Karim Benzema has endured a difficult season at Real Madrid
Zidane now faces a fight to land a first league title since Jose Mourinho ruled the roost back in 2012.
And Spanish outlet Don Balon claim three players could be sold at the end of the season if they continue to struggle.
Among those is Barcelona and Arsenal target Isco.
Isco has endured a nightmare season under Zidane and, with his contract expiring next summer, could be offloaded should he continue to struggle.
Real Madrid boss Zinedine Zidane has also grown tired of Danilo
Karim Benzema’s performances are also said to have concerned Madrid chiefs.
The France international has scored 12 goals in 26 games but has cut a frustrated figure throughout their recent plight.
That, coupled with his failure to step up in the absence of Gareth Bale, means a summer move could be on the cards.
Zidane is also growing tired of defender Danilo, who toiled during their recent Copa del Rey exit to Celta Vigo.
However, Isco and Benzema’s attitudes are causing the most friction in Spain and they could be off should they fail to raise their game.