The 2014 Barclays ATP World Tour Finals will be played at the O2 Arena in London, between 9 and 16 November.
The eight players qualified are split into two groups of four and compete in a round-robin format. The two players with the best results in each group progress to the semifinals, where the winners of a group face the runners-up of the other group. This stage, however, is a knock-out stage.
Marin is placed in Group A, with Stanislas Wawrinka, Tomas Berdych and Novak Djokovic.
Roger Federer, Kei Nishikori, Andy Murray and Milos Raonic are placed in Group B.
For his first qualification, Marin will open his campaign on Monday, November 10, at 20.00 local time (21.00 CET) against the World N°1 Novak Djokovic.