Cristiano Ronaldo may be enduring his toughest campaign at Real Madrid since arriving in 2009, but the Portugal superstar is not to blame for Los Blancos' disappointing performances, according to Deco.
Forward Ronaldo's stunning performances since moving from Manchester United have seen him collect four Ballons d'Or, two LaLiga titles and three Champions League crowns.
He has failed to reach the heights of previous campaigns this term, though, despite finding the net on 23 occasions in all competitions.
Ronaldo's personal slump has coincided with Madrid's struggles under Zinedine Zidane, with the reigning European champions sitting 17 points adrift of league leaders Barcelona having been beaten in the Copa del Rey quarter-finals by Leganes.
That has led some to suggest Ronaldo is to blame for Madrid's problems, but Deco - a former international team-mate of the 33-year-old - does not agree.
"I don't think he's going through difficulties," Deco told Omnisport. "The difficulties are at Real Madrid.
"Despite the fact that he's scored only 20 goals this season, he is still very effective.
"If he has two or three opportunities in a game, he'll end up scoring at least one.
"But it also all depends on what the team can create and Real Madrid have been very unstable recently. Real's performances have been at a lower level in comparison to what everybody expects.
"And it's natural that Cristiano can't make up the deficit. Football is a group game and a single player can't solve all the problems."