Amorim was shown the door on Monday after 18 months in charge at Old Trafford.
For now, U18 coach Darren Fletcher has been named as caretaker manager for the coming week amid talk of United eager to name Amorim's replacement in the coming days.
It's been suggested a more experienced caretaker will be appointed to guide the team to the end of the season before reassessing the position.
Howver, the Mirror says there is a section of the board who believe it would be best to find a long-term solution immediately - and pay what is needed to bring the new man in.
Beyond free agents Enzo Maresca, Xavi and Zinedine Zidane, United also have Oliver Glasner (Crystal Palace), Mauricio Pochettino (USA) and Thomas Tuchel (England) under consideration.
