2010-11: David Pastrnak skated for the AZ Havirov club in his native Czech Republic. He played 17 games (including one playoff contest) with the club’s U18 team and was +16 with 7 goals, 12 assists and 4 penalty minutes. Pastrnak scored 32 goals with 21 assists in 26 games with AZ Havirov’s U16 team and was +21 with 10 penalty minutes.
2011-12: Pastrnak appeared in six games with AZ Havirov’s men’s league team as a 16-year-old and was the third-leading scorer for HC Trinec in the Czech top U18 division after being loaned to the club by AZ Havirov. He represented the Czech Republic in the 2012 U17 World Hockey Challenge in Canada. Pastrnak had no points nor penalty minutes in Division 3 play with AZ Havirov. Pastrnak scored 33 goals with 13 assists and was +28 with 6 penalty minutes in 31 games for HC Trinec. he appeared in three regular season games for Havirov’s U20 team and was a key player during the relegation playoffs; scoring 10 goals with 9 assists and finishing +15 in eight games. He had 1 assist for the Czech Republic in five games at the WHC.
2012-13: Pastrnak left the Czech Republic to play for Sodertalje in Sweden; playing for the Czech national teams in the 2012 U19 World Junior A Challenge and the 2013 U18 World Junior Championship. He skated in 16 games with Sodertalje’s men’s team, including five games in the SHL Kval Series, scoring 2 goals with 1 assist and finishing -3. Pastrnak scored 14 goals with 19 assists in 40 games and was +8 with 10 penalty minutes for Sodertalje’s U20 team. He had 1 assist in four games at the WJAC and was +1 with 1 goal, 1 assist and 4 penalty minutes in five games at the U18 WJC. Pastrnak was selected by Severstal Cheropovets in the first round (34th overall) of the 2013 KHL Draft.
2013-14: Pastrnak was part of the Czech Republic’s bronze medal-winning U18 team at the Ivan Hlinka Memorial Tournament in August before returning to Sodertajle to skate in Allsvenskan. He played for the Czech U20 and U18 teams in their respective World Juniors tournaments. In 36 regular season games for Sodertalje he scored 8 goals with 16 assists and was +7 with 24 penalty minutes; missing time in February with a concussion that kept him out of the Five Nations Tournament in Russia. Pastrnak scored 1 goal with 2 assists and was +1 win five games at the U20 WJC and was an assistant captain for the silver medal-winning Czech U18 team at the WJC in Finland. he had 5 assists and was +1 with 2 penalty minutes in seven games. The Czechs lost 5-2 to the USA in the gold medal game. Pasternak was +2 with 2 goals, 2 assists and 2 penalty minutes in four games at the Ivan Hlinka tournament. He was ranked fifth amongst European skaters in the Central Scouting final rankings and was selected by Boston in the first round (25th overall) of the 2014 NHL Draft.
Pastrnak is an exciting offensive player who has flair and loves to be dangerous. He thrives in situations where he can carry the puck and dish it off when he feels fit. He tends to be strongest when incorporating an east-west game while on the attack. In the offensive zone he like to lug the puck and fake passes and shots while searching for just the right moment to make the killer play. Pastrnak controls the puck and can use his body well in protecting it. He is very agile in making his twists and turns, especially when he has the puck, and isn’t afraid to try a number of things as part of the attack. He has very good hands and craftiness once he has the puck. He likes to hound opposition players, especially defensemen, into forcing turnovers and is ready to pounce to create two-on-one or breakaway situations. Pastrnak's shot has improved in leaps and bounds and can be lethal from all over, particularly when using opponents as a screen. Some scouts feel Pastrnak hasn’t always shown the intensity to be a player in big games and that he can handle tough play but can be a perimeter player at times. His lack of size is an issue and at times he can make poor decisions in trying to make the ‘super’ pass. He can also be physically slowed down in corners and held behind the play. Defensive zone coverage is a concern and he sometimes looks to deking out defenders when a simple, effective play might be the better option.
Pastrnak signed a three-year entry-level contract with the Bruins in July 2014 and attended Boston's training camp before being assigned to the AHL's Providence Bruins at the start of the 2014-15 season. He made his NHL debut in November and skated with the Czech Republic U20 team in the 2015 World Juniors; returning to Boston following the tournament. Pastrnak has had an immediate impact in the Bruins' lineup as an 18-year-old and has been one of their top offensive threats during the push for a playoff spot. Long-term he should only improve as he physically matures and becomes more accustomed to the NHL level of play.