Real Madrid's form after Cristiano Ronaldo's departure is a "warning" to Barcelona when it comes to Lionel Messi, according to former Blaugrana player Jordi Cruyff.
Ronaldo, 33, made a surprise move from Madrid to Juventus for a reported €100million in July after spending nine seasons with the LaLiga giants.
Madrid initially struggled to cope with Ronaldo's absence and are eight points adrift of league leaders and rivals Barca - although they hold a game in hand.
Messi is contracted at Barca until 2021, but the club's former midfielder Cruyff urged them to learn from Madrid's mistakes.