Ronaldo: It is hard to watch Manchester United fall short

Cristiano Ronaldo feels Manchester United have significant work to do if they are to return to the same level they were at during his time at the club.

The Portugal international enjoyed a successful spell at Old Trafford between 2003 and 2009, winning three Premier League titles and the Champions League in his final three years before joining Real Madrid.

Ronaldo has nothing but fond memories of his time at United, but has found it tough to see them struggling in recent years after the retirement of his mentor Sir Alex Ferguson.

"For me it is hard to see that Manchester United are not at the same level as before because it is a club that I love," the 30-year-old told BBC Sport.

"Of course I want to see Manchester United at the level that it was in the past. Like, for example, Sporting Lisbon was my first professional club - I like to see the clubs that I like at the top.

"I think Manchester this season is better, but I think they still have work to do to be at the level of six, seven years ago.

"It is different. I'm not saying it's better or worse, it is just different. Many great players have retired. Sir Alex Ferguson has gone and the structure has changed, in my opinion."

Ronaldo is regularly linked with making a return to United, but he is adamant that he is happy with Madrid for now.

"As I say many, many times, the future nobody knows," continued the forward. "At this moment I am so glad and happy here in Real Madrid but the future nobody knows.

"I will say this answer all the time because the future nobody knows, but I am good here. I still have a contract with Real Madrid and I am happy here."