The 29-year-old Brazil worldwide signed for Real from Fluminense in 2007 and has helped Los Blancos win three Champions League titles and four LaLiga titles.
Marcelo, 29, will appear before the media at 1400 CET (1300 GMT) on Thursday after putting pen to paper on fresh terms with the Liga champions.
The full-back has more than lived up to the billing in the ten years since and claimed his fourth La Liga title and third Champions League crown in May.
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In total he has made 414 appearances for the 12-time European champions, scoring 28 goals in that time.
The news came on the same day that the Brazilian received a two-game ban for kicking out at an opponent during Saturday's surprise 1-1 draw against Levante.
That led to referee Alejandro Hernandez Hernandez brandishing a straight red for Marcelo, and the defender will now miss the league encounters with Real Sociedad and Real Betis as a result of his suspension.