Tkachenko made his international debut on September 20, 2014 at the FIS Cup in Szczyrk . However, he only finished 74th. In the 2014/15 season further starts at FIS Cup competitions followed. His best result was only a 43rd place on September 28, 2014 in Râşnov . That meant that he couldn't get any FIS Cup points. In February 2015 he took part in the Nordic Junior World Ski Championships in Almaty . He was disqualified in the individual competition and with the team he landed on 13th and last place. On the other hand, he started at the Nordic World Ski Championships in Falun . In the individual competition on the normal hill, he failed with a 56th place in the qualification. He did not have another use at these world championships.
2015/16
In the summer of 2015 he took part in the FIS Cup jumping again. On August 29, 2015, he succeeded in scoring points for the first time with a 17th place in Szczyrk. He also made his debut in the Continental Cup on October 3rd and 4th, 2015 in Klingenthal . He only finished 63rd twice. In further appearances in the FIS Cup and in the Continental Cup in the following winter, he could not get any more FIS Cup points and his best result in the Continental Cup was 47th place in Rovaniemi , which meant that he did not land in the points in this series of competitions . The Youth Olympic Winter Games in 2016 in Lillehammer , he finished 14th Place and in the Nordic Junior World Ski Championships in Râşnov the 48th place - in each individual competition.
2016/17
The following summer, on July 22, 2016, he made his debut in the Grand Prix in a team competition in Wisła . He and his team took tenth and last place. On December 9th, 2016 he got his first COC point at the Continental Cup in Vikersund as 30th. It remained at this one point in the 2016/17 season. On January 21, 2017 he made his debut in the team competition in Zakopane in the World Cup . He finished eleventh and last with the Kazakh team. At the 2017 Winter Universiade in Almaty , he took twelfth place in the individual competition and eighth place in both the team competition and the mixed team competition. He achieved his greatest international success at the Winter Asian Games 2017 in Sapporo , Japan , when he and the Kazakh team achieved the silver medal behind Japan and in the individual jumping on the normal hill was third behind the Japanese Yukiya Satō and Yūken Iwasa .
On January 13, 2019, he achieved his best ever World Cup result on the Trampolino dal Ben in Val di Fiemme as 33rd, even if he again missed the second round. He was able to celebrate his greatest international success to date eleven days later when he surprisingly became the first Kazakh to win the bronze medal at the Nordic Junior World Ski Championships 2019 in Lahti, Finland . In the team competitions he finished 14th (juniors) and eleven (mixed team) with the Kazakh teams. At the 2019 World Championships in Seefeld in Tirol he was 36th on the large hill, while he failed in the qualification on the normal hill. He finished twelfth with the Kazakh men's team and 13th with the mixed team, making it last.
statistics
winter Olympics
Pyeongchang 2018 : not qualified single normal hill, 49th single large hill
Kazakhstan
( Vikersund , 2019)
