Ronaldo will be 31, then, which won't exactly suit United or Louis van Gaal (providing he's still in charge), who'd be entering the last year of his Old Trafford contract.
Ronaldo needs, realistically, two more seasons in Spain if he is to overtake Raúl's Real Madrid goalscoring record. Raúl has 323 goals, followed by Alfredo di Stéfano on 305 and Carlos Santillana on 289, with the Portuguese 24 more behind. Ronaldo is a freak of nature and has scored at an astonishing 1.04 per match for Real whereas Raúl took 16 years to notch up a triple century, so he could claim the mantle this season.
United might have bought some centre-backs by 2016, which would excuse the extravagant fee Ronaldo will likely command, too.
Down south, Chelsea are interested in another Benfica prospect, 20-year-old Brazilian Anderson Talisca. José Mourinho will be hoping he's more Nemanja Matić than David Luíz. And definitely not another Anderson.
The Premier League leaders are also keen on Ross Barkley, coveted by Manchester City, and all yours for £50 million.
And Sampdoria's Manolo Gabbiadini (no, he's not the son of Marco) has plenty of admirers in England.