As a head coach, Duk won the 2000 ONEFA national championship with the Borregos Salvajes CEM before leading the Mexicas CDMX to a win in Tazón México III in 2018.
[2] Duk was hired as the first head coach of the Borregos Salvajes CEM for their debut season in ONEFA in 1994, where they began in the second-tier National Conference.
[3] Duk guided the team to a 6–1 record and an appearance in the National Conference championship game, where they lost 13–0 to the Panteras Negras UAM.
[12] Duk was subsequently offered the head coaching job of the Toros Salvajes Chapingo, but was unable to accept for personal reasons.
[21][22] In his first year at the helm, he led the team to an undefeated season capped off by a 41–15 victory over the Lobos Plateados IPN to win the FADEMAC league title.
[22][24] The Búhos subsequently won the third-tier National Central Conference title in 2022, defeating the Frailes del Tepeyac [es] 20–17 in the final.
[4] As a head coach, Duk led Team Mexico to bronze medals at the 2003 and 2007 NFL Global Junior Championships held in San Diego and Miami, respectively.
[1] He also commandeered the Mexico under-19 national team to consecutive bronze medals at the 2014 and 2016 editions of the IFAF U-19 World Championship held in Kuwait and China, respectively.