The Spaniard has been repeatedly linked with PSG, who are reportedly keen to secure his services on a free transfer when his current Old Trafford deal runs out at the end of the season.
Reports last week suggested that the 29-year-old was eager to extend his stay in Manchester and he underlined that it's not surprising to hear the rumours.
"It's logical when you have three months of contract left," he told El Periodico.
"I already knew something was going to come out. I take it as normal, I focus on playing football in the month-and-a-half that remains.
“The rest is left to my agent, both the possible renewal with United or talking to another club for my departure.
"I don't go crazy thinking about what will happen in four months," he added.
"I enjoy being at the biggest club in England; the fans love me, they have treated me phenomenally and my duty is to listen to them, although I honestly don't know what's going to happen.
"What I see myself is trying to win at Watford next week. If you deserve it and if you're an honest and hard-working person, opportunities arrive."
Herrera has scored two goals in 19 Premier League appearances but missed the Red Devils' last three matches through injury.
