During his time with multiple teams in the Liga Española de Baloncesto duiring the 2000s, Asselin and Bàsquet Manresa won the 2006–07 LEB season playoffs.
As a Liga ACB player from 2007 to 2015, Asselin had the 2007-2008 league season record in blocks and reached the Eurocup Basketball 2010–11 Quarterfinals with Asefa Estudiantes.
[6][7] He was a candidate to play basketball for the United States at the 1999 World University Games but did not make the final roster.
[8][9] At the 1998 NCAA Division I men's basketball tournament, Asselin and Michigan were defeated by UCLA in the second round.
During the 2003 National Basketball Development League draft, Asselin was picked by the Roanoke Dazzle in the first round.
[30] After ending his time at the LEB in 2007, Asselin had 894 rebounds and 684 field goals while amassing 1791 points in his 128 games with the four teams.
[31] As part of the Baloncesto Superior Nacional, Asselin scored 114 points with Gallitos de Isabela.
[31] As a member of the Liga ACB from 2007 to 2014, Asselin played in two seasons each with Ricoh Manresa and La Bruixa d'Or.
During this time period, Asselin was also with CB Murcia, Asefa Estudiantes and Assignia Manresa for one season and briefly played for Cajasol.
[37] In the duration of his ACB career, Asselin briefly played for Ukraine in 2009 as part of the Donetsk team.
That year, Asselin was signed by Foolad Mahan Isfahan as a temporary player for the Iran team.
[44][45] In 2012, Asselin was selected for Dominican Republic before qualification for the men's basketball event at the 2012 Summer Olympics started.
With Foolad Mahan Isfahan, Asselin and the Iran team won the 2013 Asian Cup final.
[51][52] At the 2015 FIBA Americas League, Asselin and Malvin reached the preliminary round played for Uruguay.