Manchester United fans have urged the club to make a move for Cristiano Ronaldo if Lionel Messi ends up joining rivals Manchester City this summer.

The Barcelona superstar handed in a transfer request on Tuesday and aims to leave the club on a free transfer thanks to a clause in his contract. Barcelona maintain that clause has expired and the matter could be resolved in court.

City and United are two of the few clubs in the world that could afford a deal to bring Messi to the Premier League and MEN Sport understands City have been confident in the past that they would be in pole position to sign the Argentina international if he ever decided to leave Spain.

If City do complete a sensational move for Messi, United fans want the club to answer back with a marquee signing of their own.

It's been 11 years since Ronaldo departed United for Real Madrid and some supporters believe the Reds should be looking to reignite the Messi-Ronaldo rivalry by luring him back to Old Trafford.