The trio have all be linked with £20m+ bids for the 22-year-old, but they may now face competition from Brendan Rodgers’ Liverpool.
The Northern Irishman is understood to be concerned at the lack of presence his side have at the base of the engine room, with unsettled captain Steven Gerrard now no longer at the peak of his physical powers.
Carvalho is seen as an option, with his bulky frame and powerful playing style attractive to Rodgers.
Sporting are also thought to be open to selling, with their previous desire to see his £37m release clause triggered having dropped in light if the financial difficulties the Lisbon side are embroiled in.
Carvalho himself has also recently admitted that he could leave his club soon:
“We all have ambitions and I hope one day to play in the best leagues in the world, the English or Spanish,” he told the Portuguese Association‘s magazine.
“It was not this year, but if I continue to do my job as I have done so, it will certainly come sooner or later.”