2010-11: Jean-Sebastien Dea played for College Charles-Lemoyne in the Quebec midget AAA league. He scored 26 goals with 29 assists and 28 penalty minutes in 42 regular season games. The Riverains finished fourth in the Reebok Division, and in five playoff games, Dea scored 6 goals with 3 assists and 6 penalty minutes. He was selected by Rouyn-Noranda in the third round (37th overall) of the 2011 QMJHL Entry Draft.
2011-12: Dea skated in 50 regular season games and four playoff contests for Rouyn-Noranda in his first QMJHL season. He scored 17 goals with 15 assists and was -5 with 42 penalty minutes during the regular season. The Huskies finished last in the West Division and were swept by Shawinigan in a first round series. Dea scored 1 goal with 2 assists and was -5 with no penalties against the Cataractes.
2012-13: Dea finished sixth in the QMJHL with 45 goals and was the Huskies’ second-leading scorer with 85 points (trailing only Sven Andrighetto (98)) as Rouyn-Noranda finished second in the West Division. Dea was one of two Huskies to skate in all 68 games and was +21 with 59 penalty minutes. Rouyn-Noranda reached the playoff semifinals against Memorial Cup-bound Halifax. Dea led the Huskies with 12 goals and was -2 with 9 assists and 24 penalty minutes in 14 playoff games. In his second year of draft eligibility, he was ranked 152nd amongst North American skaters in Central Scouting’s final rankings but was not selected in the 2013 NHL Draft.
2013-14: Dea was invited to Pittsburgh’s training camp as a free agent and was signed to a three-year, entry-level contract with the Penguins in September 2013 before being returned to Rouyn-Noranda for his third season. He made his pro hockey debut in April, following the QMJHL playoffs, skating in one game for Penguins’ AHL affiliate Wilkes-Barre/Scranton with no points nor penalties. Dea was tied with Halifax’ Nikolaj Ehlers for fourth in the QMJHL with 49 goals. He had 26 assists and was +4 with 53 penalty minutes in 65 games. The Huskies slipped to fifth in the West Division but reached the second round in the playoffs. Dea scored 6 goals with 3 assists and was +2 with 12 penalty minutes in nine playoff games.
2014-15: Dea played in 43 AHL regular season games and four playoff contests with Wilkes-Barre/Scranton in his first pro season, spending time with the ECHL’s Wheeling Nailers. He scored 10 goals with 11 assists and was +1 with 16 penalty minutes during the regular season for Wilkes-Barre/Scranton. The Penguins finished second in the East Division and reached the second round in the playoffs. Dea had no points with 2 penalty minutes and an even plus/minus in four playoff games. In 14 ECHL games he scored 4 goals with 3 assists and was +2 with 6 penalty minutes.
2015-16: Dea spent the full year with Wilkes-Barre/Scranton in his second season in the Penguins organization. He scored 20 goals with 16 assists and was +13 with 36 penalty minutes in 75 regular season games. The Penguins finished third in the Atlantic Division, sweeping Providence in a first-round series to face Hershey in the Atlantic Division finals. Through six playoff games Dea was -5 with no points and 12 penalty minutes.
A sniper through juniors, Dea is learning how to be more of a two-way threat at the professional level. He has solid skatering, good hands, and underrated playmaking ability, but he lacks game to game consistency, a trait that also plagued him through juniors. Dea also does not have an ideal build for NHL play, but seems to dodge a lot of the big body checks and keeps his head up when he has the puck. He needs to improve his consistency and learn to be a more effective two-way player.
Dea skated for the Wilkes-Barre/Scranton Penguins in 2015-16, scoring 20 goals in his second AHL season. Entering the third year of his original entry-level contract, he will look to crack the NHL club's lineup in training camp but barring any surprises or injuries he will be back in the AHL. The 22-year-old has established himself as a consistent two-way forward at the minor pro level despite prototypical NHL forward size. He projects as a lower line forward with some scoring ability.