Marcos is back in Dubai this week for the prestigious ATP World Tour 500 hard-court event. He received a wild card into the main draw and will open against Serbia's Viktor Troicki.
Marcos is making his eighth visit to the Dubai Duty Free Tennis Championships, where he finished runner-up in 2016. He owns a 4-3 head-to-head record against fellow 32-year-old Troicki, having earned a straight-set win over the Serbian en route to that final run two years ago. Their most recent encounter was on the clay of Istanbul last year.
Marcos would face either seventh seed Filip Krajinovic or Thomas Fabbiano in the second round, with fourth seed Damir Dzumhur also in his quarter of the draw. Grigor Dimitrov, Lucas Pouille and Roberto Bautista Agut are other big threats in Dubai.
Marcos opens his campaign on Monday, not before 7pm local time on Centre Court.