2009-10: Gemel Smith played for the North York Rangers midget AAA team in Ontario. In 52 games he scored 31 goals with 51 assists. He was selected by Owen Sound in the sixth round (120th overall) of the 2010 OHL Priority Draft.
2010-11: Smith skated in 66 of 68 games for the OHL champion Owen Sound Attack as a 16-year-old. He scored 8 goals with 8 assists and was plus-eight with 14 penalty minutes. Owen Sound finished first in the Midwest Division with the OHL’s second best record and defeated Mississauga St. Michael’s in overtime in the seventh game of the league championship series. Smith played in 21 of 22 playoff contests and was plus-one with 1 goal and 2 assists. In four games at the Memorial Cup he had no points and was -1 with 4 penalty minutes. Owen Sound was 1-3 in the Memorial Cup; losing to Kootenay in the tie-breaker game after shutting out the Ice earlier in the tournament.
2011-12: Smith was the third-leading scorer for Owen Sound in his second OHL season and won a bronze medal playing for Canada at the 2012 U18 World Junior Championship. He scored 21 goals with 39 assists and was plus-nine with 51 penalty minutes in 68 games for the Attack. Owen sound slipped to third in the Midwest Division and lost to Kitchener in a first round playoff series. In the five-game series Smith scored 1 goal with 2 assists and was plus-one with 10 penalty minutes. In seven games with Team Canada he scored 2 goals with 3 assists and was -1 with 2 penalty minutes. Canada defeated Finland in overtime in the bronze medal game. Smith was invited to the NHL Draft Combine and ranked 37th amongst North American skaters in the Central Scouting and was selected by Dallas in the fourth round (104th overall) in the 2012 NHL Draft.
2012-13: Smith was the third-leading scorer for the Owen Sound Attack, which finished second to OHL champion London in the Midwest Division. He scored 23 goals with 29 assists and was +17 with 54 penalty minutes in 61 games. Owen Sound had the OHL’s third-best record and reached the second round in the playoffs. Smith led the Attack with 7 goals in the playoffs and also had 3 assists; finishing -2 with 10 penalty minutes in 12 playoff games.
2013-14: Smith attended the Dallas Stars training camp before returning to Owen Sound for his fourth OHL season; skating in 40 games for Owen Sound before being acquired by Memorial Cup host London. In 69 OHL regular season games between the Attack and the Knights he scored 37 goals with 38 assists and was -1 with 47 penalty minutes. London finished third in the Midwest Division behind OHL champion Guelph and Erie and reached the second round in the playoffs. Smith scored 3 goals with 9 assists and was +4 with 9 penalty minutes in nine playoff games. In three games at the Memorial Cup, all Knights’ losses, he was -2 with no points and 10 penalty minutes. Smith signed a three-year entry-level contract with the Stars in May 2014.
2014-15: Smith competed for the Stars in the 2014 Traverse City rookie tournament and attended Dallas’ training camp before being assigned to AHL affiliate Texas to start the 2014-15 season. Skating in 68 games for Texas he scored 10 goals with 17 assists and was +9 with 38 penalty minutes. The Stars finished second in the West Division and were swept by Rockford in a first-round playoff series. Smith did not appear in any playoff games.
Smith was one of the fastest players taken in the 2012 draft. He is an energy player that makes the Energizer Bunny look like a tortoise and is an annoying player, constantly in the opposition’s face. Despite lacking size he is physical and tenacious. His feet never stop moving and he wins a lot of battles by that virtue. Smith is a strong forechecker that can fly back to cover defensively. Most of his scoring comes from turnovers he forces. He doesn’t possess elite offensive skills but has some good passing ability. Smith won’t score any goals from far-out because of a lacking shot. He will need more bulk and strength at the pro level but not at the cost of his speed. He is probably better suited as a wing at the next level.
Smith is skating for Dallas AHL affiliate Texas in 2015-16. Briefly demoted to the ECHL's Idaho Steelheads for a four-game stretch, he has played mostly in a lower line role with the Stars but has chipped in offensively on occasion. Now in the second year of his original entry-level deal, Smith's energy and skating ability suggest he can be an effective bottom-six energy player in the NHL.