2008-09: Dmitri Jaskin played for HC Slavia Praha in the Czech U-18 league. In 46 games, he scored 28 goals and added 19 assists for 47 points to go along with 34 penalty minutes. In 9 playoff games, Jaskin scored 6 goals and added 2 assists for 8 points.
2009-10: Jaskin again played for the HC Slavia Praha organization, this time splitting time between the U-20 and U-18 squads. In 40 games for the U-20 club, he scored 13 goals and added 10 assists for 23 points to go along with 67 penalty minutes. In 7 playoff games, he scored 2 goals and added 5 assists for 7 points to go along with 26 penalty minutes. For the U-18 squad, Jaskin scored 15 goals and added 112 assists for 27 points to go along with 36 penalty minutes. In 2 playoff games, he scored 1 goal and added 3 assists for 4 points. Jaskin was chosen in both the CHL Import Draft (Calgary Hitmen) and the KHL Junior Draft (Sibir Novosibursk).
2010-11: Jaskin moved up to HC Slavia Praha's top team, playing in 33 games for that team. He scored 3 goals and added 7 assists for 10 points. In 17 playoff games, Jaskin scored netted 2 goals and added 1 assist to 3 points to go along with 31 penalty minutes. Jaskin played for the Czech Republic at the 2011 U-18 World Junior Championship, scoring 4 goals and adding 1 assist for 5 points in 6 games.
2011-12: Jaskin played in 30 games for Slavia Prague in the Czech Extraleague and also played for HC Berounsti Medvedi in the Czech second league. He skated in the 2012 U20 World Junior Championship and was dominant in a dozen games playing in the Czech U20 junior league. He had 1 goal with 1 assist for 12th place Slavia Prague; finishing minus-seven with 16 penalty minutes. Jaskin saw more ice time during the relegation playoffs, scoring 3 goals with 1 assist in seven games and finishing plus-2 with 2 penalty minutes. In 10 games with Medvedi he scored 2 goals with 6 assists and was an even plus/minus with 16 penalty minutes. In five games for the fifth-place Czech Republic U20 squad he scored 1 goal with 1 assist and was plus-one with 4 penalty minutes. He skated in 12 games (including two playoff games) for Slavia's U20 team and was plus-nine with 7 goals and 14 assists. He was selected by Moncton in the first round (12th overall) of the 2012 CHL Import Draft and will play in the QMJHL in 2012-13.
2012-13: Jaskin signed a three-year entry-level contract with St. Louis in April 2013 and made his NHL debut with the Blues after playing for the QMJHL's Moncton Wildcats in his first season in North America. He was -1 with no points nor penalty minutes, averaging 7:29 minutes of ice time, in two games with St. Louis and was with the Blues during their playoff series with Los Angeles but did not appear in any games. He scored 46 goals with 53 assists and was +26 with 73 penalty minutes in 51 regular season games for Moncton; missing time to skate for the Czech Republic in the 2013 World Junior Championship. The Wildcats finished second in the Maritimes Division and lost to Victoriaville in a first round playoff series. Jaskin scored 1 goal with 2 assists and was +1 with 16 penalty minutes in five playoff games. He scored 3 goals with 3 assists and was +3 with 12 penalty minutes in six games for the Czech Republic at the WJC.
Jaskin is a big, strong boy and when he's on, defenders have a difficult time stopping him and he's nearly impossible to bump off the puck. He also has a mean streak, never backing down when challenged, which can sometimes get him into penalty trouble. Some scouts have also questioned whether he is always motivated to play, as he tends to be a streaky player.
Jaskin put himself on the map with the Moncton Wildcats of the QMJHL in 2012-13. His arrival from Europe was long awaited, and he did not disappoint. He dressed in two games for the Blues but will likely play in the AHL in 2013-14 to get a feel for the professional game in North America.