Lazio midfielder Luis Alberto has warned Real Madrid that Atalanta will be no easy task on Wednesday night.
Los Blancos are already in Bergamo ahead of the first leg of their Champions League last-16 tie, and the 28-year-old said they will need to be on their game.
"People need to know it won't be easy," Luis Alberto told MARCA.
"Atalanta push you to the limit, and if you don't compete you're dead, because they'll keep chipping away.
"If Real Madrid compete well, with the quality they have, they should advance to the quarters."
Luis Alberto is sure that Zinedine Zidane will be well prepared, but he knows a thing or two about getting a result at Atalanta himself.
Just last month, the Spaniard made his comeback from injury in Lazio's 3-1 win away at Atalanta, so Los Blancos would do well to listen to his advice.