The report claims that both the clubs have approached the Napoli striker, as they want to snap him up on free next summer.
Mertens is out of contract in June and has been unable to sign an extension at the Naples club.
While the Blues will battle it out to agree a deal in January ahead of a summer move, Everton must move quickly to bring him to Merseyside this month.
The Belgian attacking midfielder is a world-class player and Ancelotti knows him very well. He is a versatile attacker who can play across all three positions – left, right and centre – upfront.
Having represented the country 86 times, and played over 590 senior games in club football, he has got loads of experience, something Ancelotti should look to bring at Goodison Park as he prepares to build squad according to his own taste.
At 32, he is still going strong. He has scored nine goals and provided three assists in all competitions for Napoli, and there’s still a lot of football left in him.
With his contract running down, Everton can get him at a cut-price deal. For a player of his experience and ability, Ancelotti would seal a masterstroke signing if the Toffees can move ahead of Chelsea and bring him to Goodison Park in January.