Top seed Jelena Ostapenko wasted two match points as she was sent crashing out of the Bogota Open in the first round after a thrilling fightback by world number 205 Kristie Ahn.

Ranked 176 places below the 2017 French Open Champion, Ahn fought back from the brink in the deciding set to record an unlikely 2-6 7-6 (7-5) 7-5 victory in two hours and 31 minutes in Colombia.

World number 29 Ostapenko had raced to a ruthless 4-0 lead before taking the first set 6-2. The 21-year-old Latvian was all set for a swift victory after breaking Ahn to go up 4-2 in the second.

But it was then the comeback began as the American lucky loser, who was beaten 7-5 6-4 by 162nd-ranked Bibiane Schoofs in qualifying, recovered to force a tie-breaker that she clinched 7-5.

In a back-and-forth decider, Ostapenko failed to convert a pair of match points before 26-year-old Ahn completed the epic comeback to claim her first win of the season in a main draw.

In other first round matches on Tuesday, there were wins for the seventh seed Sara Sorribes Tormo, 6-4 6-4 over Christina McHale, and Magda Linette (8), who overcame Aliona Bolsova Zadoinov 2-6 7-6 (7-5) 6-0.

Lara Arruabarrena (11) downed Timea Babos 6-7 (7-9) 6-4 6-1 and Sara Errani came through a three-set tussle with Irina Bara 4-6 6-2 6-3.