He has played in the National Hockey League for the San Jose Sharks, with his NHL debut coming during the 2008-09 campaign, Carolina Hurricanes and the Vancouver Canucks.

After finishing his OHL career he played in the American Hockey League (AHL) for the Worcester Sharks, where he was also an All-Star.

[3] Joslin was selected in the 10th round, 200th overall, of the 2003 Ontario Hockey League (OHL) priority draft by the Ottawa 67's.

[6] Since London was the host team for the 2005 Memorial Cup the 67's qualified for the tournament as the OHL representative despite their loss.

[8] During the OHL playoffs and Memorial Cup Joslin played sparingly due to a broken Scaphoid bone.

After the 67's were eliminated he made his professional debut playing two games for the American Hockey League's (AHL) Cleveland Barons.

[6] Joslin finished the season with almost identical scoring stats registering 11 goals, 38 assists and 49 points.

[2] Joslin started the following season with Worcester after being one of the last players cut from San Jose's training camp.

[15] Following an injury to San Jose defenceman Douglas Murray, Joslin made his National Hockey League debut January 3, 2009, in a game against the New York Islanders.

[6] Although he was regularly a healthy scratch playing in only 17 for San Jose before a February 18, 2011 trade sent him to the Carolina Hurricanes in exchange for future considerations.

[19] During the first season of his new contract Joslin fell behind other defenceman on the depth chart and was regular healthy scratch, only playing in 14 of the first 41 games.

[21] He finished the season playing in an NHL career high 44 games scoring 2 goals and 4 points.

[23] Due to the 2012–13 NHL lockout he was assigned to the Canucks' minor league affiliate, the Chicago Wolves, at the beginning of the season.

On July 28, 2013, Joslin left North America and signed his first European contract on a one-year deal with AIK IF of the Swedish Hockey League (SHL).

[28] Following his year in Sweden, Joslin took his game to Germany, where he signed with the Nürnberg Ice Tigers of the Deutsche Eishockey Liga (DEL) for the 2014–15 season.