The 21-year-old had been attracting interest from a host of top clubs in recent weeks, including Arsenal, Monaco and Paris Saint-Germain, before moving to Marseille in the summer.
The France Under-21 international, who scored five goals in 108 top-flight appearances for Guingamp before moving to l’OM, has already scored once in seven appearances for his new club.
And Chelsea scout Hillion has revealed the Blues are still tracking the up-and-coming les Bleus star ahead of the January transfer window.
“I have seen [Imbula] often,” Le10Sport quotes Hillion as saying. “As soon as he gets the ball, he is able to accelerate and break through the lines.
“He covers well, has good technique, great vision of the game, with a very good quality pass and a great left foot. He doesn’t have bad qualities for a midfielder.”
José Mourinho’s men are in fifth place following a 3-1 victory over Norwich City at Carrow Road in the Premier League on Sunday.
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