Cristiano Ronaldo has refused to rule out a return to Manchester United. The 29-year-old, who left Old Trafford in 2009, was linked with a move back last summer before signing a new long-term deal at Real Madrid. He's under contract at the Bernabeu until 2018, by which time he'll be 33. But asked ahead of Real's clash with United in Michigan whether he could ever see himself returning to the club he joined from Sporting Lisbon in 2003, the Portuguese forward claimed anything is possible.