Two of Jose Mourinho’s scouts were sent to watch last week’s Champions League game between Roma and Atletico Madrid.
They were monitoring the progress of a midfielder on each side – Saul Niguez, 22, and Radja Nainggolan, 29.
Captain Carrick is 36 and this is expected to be his last season as a United player.
The midfielder joined the Red Devils in 2006 from Tottenham and has so far made a total of 459 appearances for United.
Mourinho, meanwhile, leads his side into battle with Everton at Old Trafford this afternoon insisting the Premier League is the hardest division in the world to win.
The United boss said: “This is the country with more teams that fight for the title.
“Also, teams outside that group of six or seven can take points off you.”
