Guillén won the 2008 Central American and Caribbean Championship held in
Trinidad and Tobago returning to the same venue shortly afterwards to win the 2008 Pan American Championship. For her performance during the 2008 year, she was selected by the Dominican Republic Boxing writers "Female Boxer of the Year". She competed at the
2010 AIBA Women World Boxing Championships, but was defeated by the Dutch boxer
Nouchka Fontijn in the first round of the preliminary round. At the 2nd Panamerican qualifier held in
Ecuador, Yenebier earn the gold medal and the ticket to the
2011 Pan American Games. There, she planned to qualify to the
2012 Summer Olympics. and finally won the silver medal after losing 15-11 from the Canadian
Mary Spencer. Early 2012, Guillén received the 2011 Athlete of the year in Boxing award from the
Dominican Republic Olympic Committee. In
Qinhuangdao, Guillén after winning the first two rounds, lost 11–13 in her Round of 32 debut match of the
2012 AIBA Women's World Boxing Championships to Poland's
Lidia Fidura.
2013 Guillén started 2013 by winning the gold medal at the Copa Independencia Nacional, held in Santiago, Dominican Republic. There she won 21–5 against the Venezuelan Francelys Carmona. During the AIBA Women's Pan American Championship in May, Guillén overcame the three times world champion Mary Spencer in the semifinals before defeating 15–7 to the American Franchon Crews in the gold medal combat. In November, Guillén had to settle with the silver medal during the La Romana Tournamente, celebrated in La Romana, Dominican Republic, when she lost 1-2 from the Panamanian Atheyna Baylon. Later that month, she won the gold medal at the
2013 Bolivarian Games held in Trujillo, Peru. She defeated 3–0 to the Colombian Jessica Caicedo in the final.
2014 For her merits during the 2013, Guillén was awarded Female Boxer of the Year award by the Dominican Republic Boxing Federation, and American Confederation of International Boxing Association's Female Boxer of the Year Guillén won the gold medal in the first qualification for the Central American and Caribbean Games held in May in Tijuana, Mexico, when she defeated 2–1 to the Panamanian Atheyna Bylon. Later she repeated the gold medal in the Venezuelan competition Batalla de Carabobo, She then participated in the
Pan American Sports Festival, winning the silver medal after losing to the American Claressa Shield. Guillén defeated the Mexican Alma Ibarra to win the 75 kg gold medal at the
2014 Central American and Caribbean Games in Veracruz, Mexico.
2015 Guillén competed in
boxing at the 2015 Pan American Games – Women's light heavyweight. She reached the gold medal final but was defeated. ==References==