What Manchester United fans would do to see Cristiano Ronaldo back at Old Trafford.

The rumours linking the Portuguese star with a return to Manchester, which were prevalent last year, have been nothing short of a pipe dream.

Even the most optimistic United supporter knew that. But it wouldn’t have stopped them dreaming.

United fans have fond memories of Ronaldo’s six seasons at the club from 2003 to 2009. He helped the Red Devils, then managed by Sir Alex Ferguson, to three Premier League titles and opened the scoring in the 2008 Champions League final over Chelsea, which United went on to win in a shootout.

Ronaldo has reached even greater heights since signing for Real Madrid eight years ago. And while he’s flourished in Spain, United have lost their way somewhat, appointing three different managers and failing to finishing higher than fourth since Ferguson retired in 2013.

Ronaldo is hopeful that Jose Mourinho, who replaced Louis van Gaal last summer, can restore United’s identity as one of Europe’s strongest sides.

"If it's something United wanted I think it's good - I hope Manchester United get back to what they were because it's an impressive club but in the last years they lacked an identity a bit,” Ronaldo said last year, via Sky Sports.

"And it hurts me seeing United like that because it's a club I carry in my heart. I wish Mourinho can restore them back to the top."

Ronaldo's best United moment

Ask any United fan to recall their favourite Ronaldo moment and you’ll get a variety of answers.

The free-kick against Portsmouth in 2008. The 40-yard screamer against Porto a year later. The hat-trick against Newcastle United, the one and only hat-trick of his United career.

Rooney's rash tackle on Ronaldo

One moment that isn’t quite as well remembered is his meeting against Wayne Rooney in 2003. Rooney would join Ronaldo at Old Trafford a year later but for now, the Portugal international was his opponent.

Ronaldo didn’t score as United ran out 3-2 winners but he still enjoyed a fine performance, as the highlights show.

The 32-year-old, just a teenager at the time, was even scythed down by Rooney just before the hour mark.

Watch how Rooney introduced himself to Ronaldo in the video below (at 4:58).

Watch: Ronaldo, meet Wayne

Ronaldo will have had some words for the England international upon his arrival at United the following summer.

What is your favourite Ronaldo moment at Man United? Let us know in the comments section below!