The Sri Lanka Athletics Association tabbed Merrill as the country's female wild card entrant on Monday. The SLAA had sent her name for IAAF consideration after none of Sri Lanka's female athletes had reached Olympic qualifying standards before the deadline closed on Sunday.
An eight-time All-American during her four-year career with the Tritons, Merrill was picked ahead of three other female athletes, who had been shortlisted.
She will compete in the 400-meter hurdles beginning on Sunday, August 5 at Olympic Stadium in London.
"A big thank you to Sri Lanka for selecting me as their top female athlete," Merrill posted on her Facebook page. "And a bigger thank you to all of you who helped me get here!! Talk about dreams coming true."
Merrill, an American whose mother Neloufa is from Sri Lanka, represented the island nation at both the Asian Athletics Championships and the IAAF World Championships last summer. She claimed a bronze medal with a time of 57.30 at the Asian Championships and set a new Sri Lankan national record after clocking in at 56.83 in prelims.
She went on to finish sixth in her heat at the World Championships at 57.05 the following month.
One of the most successful athletes in program history, Merrill set school records in both the 400 hurdles (58.04) and 400-meter dash (54.76) as a senior at UCSD in 2010. As a junior, she won the NCAA Division II title in the 400 hurdles after posting a first place time of 58.59 in San Angelo, Texas.
Merrill graduated from UCSD in the spring of 2010 with a degree in mechanical engineering.
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