In an interview that was released after being dropped for the Manchester derby win over City on December 15, the 27-year-old said he was 'ready for a new challenge' and was prepared to leave United.
As a result, he was then left out of the squad to face Spurs in the Carabao Cup, a 4-3 quarter-final defeat, and the 3-0 loss at home to Bournemouth at the weekend.
That has now fuelled rumours that Rashford could leave the club in January, while it remains uncertain if he will be recalled to the squad to face Wolves.
"It is a hard situation," Amorim said.