The Chile international has been heavily linked with a move to Old Trafford, but the midfielder's recent knee surgery is said to have raised concerns over the deal.
However, reports have claimed that the former Premier League champions are willing to part with £40m and Hernandez, who has fallen down the pecking order at United in recent seasons.
According to The Express, when asked about the potential transfer, the striker's agent said: "For now I cannot comment on the situation.
"I have no news at the moment on an exchange, I haven't spoken to anyone in England, but there will be news soon."
The 26-year-old joined the North-West outfit back in 2010.