Rumours suggest that Los Che have agreed a £20m deal for the Argentine, and that they are confident of snapping him up to kick-start their new era under owner Peter Lim.
But United – who have been tracking the South American for some time – are now ready to go in over the Spaniards’ heads with a bigger offer.
Reports suggest that they’ve contacted Benfica to assess the likelihood of a bigger offer being successful, and could launch their own raid as Louis van Gaal plots to overhaul his inherited squad.
Perez is currently away at the World Cup, but before the competition he stated that he would respect the Portuguese giants’ decision if they opt to sell him:
“I am very happy at Benfica, I signed the contract renewal before travelling to join the Argentina squad, which shows that I want to keep wearing this shirt.
“I am feeling very well at Benfica and I know the club will try to do the best for me. I’ll respect what they decide.”