That’s according to European football expert Raphael Honigstein, who claims Real have never really been convincing under the 1998 World Cup winner.
The reigning La Liga champions dropped to a shocking 2-1 defeat to Girona on Sunday, leaving them eight points behind rivals Barcelona.
Cristiano Ronaldo has been clinical in front of goal in the Champions League but hasn’t been able to replicate that form in the league with just one goal in six games.
And Honigstein believes it could be only a matter of time before Real president Florentino Perez presses the panic button if Zidane doesn’t start getting results in the league.
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Zidane has his work cut out
"Managers have been fired for far less misdemeanours than finishing eight points behind Barcelona. It’s unforgivable,” Honigstein told BBC Radio 5 Live.
"Everything he’s done before will count for absolutely nothing if he doesn’t improve the league form.
“In the Champions League, Real Madrid might still win it again, despite being underwhelming. That’s what they’ve done over the last few years.
Zinedine Zidane is under increasing pressure at Real Madrid
Cristiano Ronaldo has scored just one La Liga goal this season
“They have never completely convinced us apart from maybe individual games.
“But it’s with the Barcelona that’s been mostly written off before the season that the comparison looks very bleak.
“So Zidane has his work cut out, absolutely.”