http://www.bbc.co.uk/sport/0/football/26867861Wayne Rooney is not world class - Joey Barton
Manchester United forward Wayne Rooney lacks the mentality to become a "world-class" player, says Queens Park Rangers midfielder Joey Barton.
Rooney, 28, recently signed a new contract that puts him among the highest-paid players in football.
But Barton told BBC Radio 5 live that Rooney's mental approach leaves him behind the world's best on the pitch.
"Rooney is world class - potentially - but his mentality is the polar opposite to Cristiano Ronaldo's," Barton said.
The 31-year-old added: "Why is Ronaldo a Ballon d'Or winner and Rooney isn't? Players who have worked with both say the level of discipline Ronaldo has is the reason he is where he is."
Ronaldo, 29, scored his 14th Champions League goal of the season to equal a record set by Barcelona's Lionel Messi as Real Madrid defeated Borussia Dortmund 3-0 in their Champions League quarter-final first leg at home on Wednesday.
Rooney scored his 17th of the campaign in all competitions with a brace as United beat Aston Villa 4-1 at Old Trafford on Saturday.
"When you see Rooney smoking cigarettes," Barton continued, "is he doing everything he can to be the best player in the world? The gulf is getting wider."
The former Newcastle, Manchester City and Marseille player later tweeted: "I would have to argue that he has not been better since he broke on the scene at Everton. For me that is when he stopped developing."