Marcos suffered a first-round exit at the Australian Open on Monday evening, falling to talented Uzbekistani Denis Istomin 6-4, 7-5, 6-4 in two hours and 36 minutes.
Marcos fought hard in the contest, rallying from an early break down in the second set to push it close and saving two match points in the final game before eventually succumbing.
Istomin was strong on serve, fending off eight of the nine break points he faced and making 77 per cent of his first serves.
It is the first time in 10 appearances at Melbourne Park that Marcos has fallen in the first round. He dropped to a 22-10 tournament record.
