Hammond told The Reading Chronicle: "We're desperately keen to keep Nicky here but success brings interest from elsewhere and we have to accept that.
"However, we have to do what's right for Reading and selling Nicky in the transfer window wasn't right, certainly not for the money offered.
"We had a written offer a week before last Friday's deadline which was way beneath our valuation. We refused it and we received no further offers after that.
"Nicky is a bright lad. He understands that if we don't get a realistic offer there is no decision to make. But I felt it was completely wrong to sell him.
"Now this gives us more time. We'll let the dust settle then return to Nicky and try to persuade him to stay.
"If he's still of the mindset that he doesn't want to commit to us, we will have to see where we are in the next transfer window or next summer.
"But he is a fantastic professional and he will continue to perform for us at the highest level while he's a Reading player."