In his first year as a senior athlete, he set a personal best of 57.57 m and won the discus title at the 2007 ALBA Games.[4] He cleared the 60 m mark numerous times in 2008, setting a new personal best of 63.31 m in Havana in June.[5] He was chosen to compete at the 2008 Central American and Caribbean Championships and came away with the gold medal, finishing just ahead of fellow Cuban Yunior Lastre.[6] Fernández made his Olympic debut at the age of twenty a month later and finished 15th in his qualifying group at the 2008 Beijing Games.[1]
His 2009 season was entirely based in Havana: he won the discus titles at the 2009 ALBA Games and then the Barrientos Memorial.[4] He threw a new personal record mark of 63.92 m in June.[5] The 2009 CAC Championships was held in the Cuban capital and he defended his region title to lead a discus 1–2 for the host nation alongside his compatriot Lastre.[7] In the early part of 2010, he had a throw of 64.13 m then threw 66.00 m exactly in March in Havana. He won the Barrientos meet and the national championships before going on to take the bronze medal for Cuba at the 2010 Ibero-American Championships in Athletics in San Fernando, Cádiz.[4] At the end of the track and field season, he was selected to represent a combined Americas team at the 2010 IAAF Continental Cup and he finished the competition in sixth place with a throw of 61.18 m.[8]
Fernández started the 2011 season in strong form, throwing 65.54 m at the Copa Cuba meeting in March and winning at the Barrientos Memorial with a throw of 64.77 m in May.[9][10] In his first year based in Europe, he had a season's best throw of 65.89 m came in Cottbus in June and won the Weltklasse in Biberach and Meeting de Atletismo Madrid competitions.[4][11] At the 2011 World Championships in Athletics he was fourth in qualifying with a mark of 64.94 m, but fell short of this in the final, ending the final in eighth place with a best mark of 63.54 m.[4] His year ended on a high as he won the gold medal at the 2011 Pan American Games in Guadalajara – his winning throw of 65.58 m was the best seen at the tournament in 24 years and he became the third Cuban to take the men's Pan American discus title (joining Roberto Moya and Luis Delís).[12]