Jackman first started playing Junior "A" and "B" with his hometown's Trail Smoke Eaters and the Beaver Valley Nitehawks in the 1996-97 season.

Jackman won the Calder Memorial Trophy (Rookie of the Year) in 2003, narrowly beating out the Detroit Red Wings' Henrik Zetterberg and the Columbus Blue Jackets' Rick Nash.

He was a member of the 2007 Canadian IIHF World Championship team that won gold in a 4–2 win against Finland in Moscow, Russia.

[2] On June 11, 2015, Jackman was informed by the Blues that his association with the club after 16 years would end, releasing him to free agency.

On July 1, 2015, Jackman signed with Central Division rivals the Nashville Predators on a two-year contract, worth an average of $2 million per season.