Cristiano Ronaldo's obsession with Lionel Messi is having an adverse effect on Real Madrid and the club should consider selling him, according to Barcelona legend Hristo Stoichkov.

Three-time Ballon d'Or winner Ronaldo has endured a turbulent few weeks in the Spanish capital where he has struck just three goals in his last seven games, a poor return by his remarkably high standards.

And with fresh doubts now emerging over the player's happiness at the Santiago Bernabeu, five-time La Liga winner Stoichkov believes now is a better time than ever to cash in.

"I don't know if they are short of money," Stoichkov told Sportium. "If they are, it is a good moment to sell him."

Ronaldo was also criticised for his reaction to Gareth Bale's first goal for Real Madrid in a 2-0 win over Levante on 14 March.

Bale, who has struggled with a goal drought of his own, netted the first of his double after Ronaldo saw his bicycle kick deflected off-target in the build-up. Ronaldo, instead of celebrating with the Welshman, instead threw his arms in the air in frustration having seen his own effort blocked.

Stoichkov said of the incident: "You can never get angry because a teammate has scored and not celebrating is to commit suicide as a teammate, because then you are worth nothing and you are worth nothing to your team."

Since winning his second consecutive Ballon d'Or title on 12 January, Ronaldo's form has noticeably dipped. His haul of 10 goals in all competitions since that date remains one of the best returns in Europe, but it is bettered by Messi's tally of 19 in the same period.

Stoichkov believes Ronaldo has developed a deep obsession with being better than the Argentine superstar, something that may come at a detriment to his teammates.

"You can't doubt the quality of either Ronaldo or Messi. Messi is where he should be and Cristiano is going through a difficult time, but all players go through rough patches. I was whistled as well in my time. It is up to the coach to make decisions and to speak to the player.

"Maybe the obsession with Messi is affecting him, but I am not in his head. Messi motivates his teammates and if Ronaldo doesn't score it affects his team."