Hickey found a home as an effective two-way defenseman with the New York Islanders after developing a steady, reliable game in his own zone to go along with excellent puck-moving skills.
As a junior, Hickey's elite offensive game with Seattle of the Western Hockey League helped make him the fourth player chosen in the 2007 NHL Draft, when he was selected by the Los Angeles Kings. Hickey appeared in five games as a 15-year-old with Seattle in 2004-05, scoring twice and ending with three points. He became a regular the next season, led all Seattle defensemen in scoring with 28 points and was named the team's Rookie of the Year.
Hickey found a home as an effective two-way defenseman with the New York Islanders after developing a steady, reliable game in his own zone to go along with excellent puck-moving skills.
As a junior, Hickey's elite offensive game with Seattle of the Western Hockey League helped make him the fourth player chosen in the 2007 NHL Draft, when he was selected by the Los Angeles Kings. Hickey appeared in five games as a 15-year-old with Seattle in 2004-05, scoring twice and ending with three points. He became a regular the next season, led all Seattle defensemen in scoring with 28 points and was named the team's Rookie of the Year.
Hickey was named a WHL Second-Team All-Star in 2006-07 after finishing with 50 points and a team-high 41 assists; he was tied for eighth in scoring among defensemen and sixth in assists. Hickey returned to Seattle for two more seasons after being drafted, and his offensive game continued to improve. He was a WHL First-Team All-Star in 2007-08 after scoring 11 goals and finishing with 45 points and a plus-20 rating. Hickey also won a gold medal playing for Canada at the 2008 World Junior Championship.
He was captain of Seattle in 2008-09, his final season in junior, and again earned WHL First-Team All-Star honors with 16 goals, 51 points and a plus-37 rating. He also captained Canada to a second straight gold medal at the 2009 World Junior Championship.
Hickey made his professional debut with Manchester, the Kings' American Hockey League affiliate, at the conclusion of the 2008-09 season, finishing with one goal and seven points in seven games.
But injuries stalled Hickey's career. He had a shoulder injury in November 2009 that required surgery and kept him out for more than four months. He also missed Manchester's first 12 playoff games because of an ankle injury.
After two more seasons in Manchester, the Kings placed Hickey on waivers in January 2013, the Islanders claimed him and he made his NHL debut on Jan. 27, 2013. Hickey got his first goal on Feb. 21, 2013, when he scored against Carey Price of the Montreal Canadiens in overtime.
Hickey helped the Islanders reach the Stanley Cup Playoffs in three of his first four seasons. He scored his first career playoff goal on April 17, 2016, when he beat Roberto Luongo of the Florida Panthers in overtime to win Game 3 of their Eastern Conference First-Round series.