Gareth Bale's agent has slammed Jorge Valdano as "nothing" after the former Real Madrid sporting director heavily criticised the Wales international's performance in Sunday's 5-1 defeat at Barcelona.

Bale started the match at the Camp Nou but was substituted on 76 minutes with his side 3-1 down.

And Valdano pointed to the Wales international's lack of tactical discipline as one of the major problems as Madrid have had their worst start to a season in La Liga in over 50 years.

"Bale is one of many players at Madrid who play very freely," Valdano told Onda Cero. "He had the job to follow [Barca left-back] Jordi Alba, and his concentration lasted just seven minutes.

"Alba was completely free to set up the first goal. There are players in the squad who, like Bale, think they are so important they can do whatever they want. That goes against the collective."

However, Bale's agent, Jonathan Barnett was unimpressed with the comments, and told Valdano exactly how highly he valued the Argentine's opinion.

"It comes from nothing so it is taken as nothing," Barnett said when asked about the comments by ESPN FC.

Valdano, a World Cup winner in 1986 with Argentina, also said that, despite Bale providing some important moments for Madrid during his first five seasons at the club, he had still not lived up to then world record €101 million price-tag.

"Bale's price left the fantasy that he is world class," Valdano said. "But his last five seasons do not match what Real Madrid paid for him.

"He can score the goal of the season any year, and that must be applauded, but [other players like] Sergio Ramos are consistent throughout the season and have also scored historic goals for Real Madrid."

Bale has won 14 trophies including four Champions League titles since joining from Tottenham in summer 2013.

Barnett told ESPN FC that Bale had nothing to say about the coaching situation at the club -- with summer arrival Julen Lopetegui thought to be close exit door and ex-Chelsea manager Antonio Conte lined up to take over.