The Chilean seemed destined for a move to the Etihad, having almost signed for Pep Guardiola's side on the final day of the summer transfer window, only for Arsenal's failure to secure a replacement to scupper the deal.
Now, though, through putting a more attractive proposal to Sánchez and offering Henrikh Mkhitaryan in exchange to the Gunners, United are set to announce the 29-year-old as their latest signing.
But what will Sánchez bring to Old Trafford? And where will he fit into José Mourinho's side?
Sánchez may not have been in peak form for Arsenal this term but, as Ryan explains, he has all the tools to transform United's attack.