In 2015, he moved to Tercera División side Atlético Tordesillas, and made his senior debut on 23 August of that year by playing the last ten minutes of a 1–0 home defeat of CD Palencia Balompié.
In July 2016, Marcos signed for CD Cristo Atlético still in the fourth division.
[2] Roughly one year later he moved to CD Numancia, being assigned to the reserves in the same category.
[3] Marcos made his professional debut on 13 September 2018, starting and scoring his team's only in a 1–2 home loss against Sporting de Gijón, for the season's Copa del Rey.
[5] On 16 January 2020, after making no league appearances during the campaign, Marcos was loaned to Segunda División B side CD Tudelano until June.