A former member of the Czechoslovakian U17 national team, Ján began playing hockey in Iskra Banska Bystrica. Ján was a member of the junior team that won the Czechoslovakian championship in 1991/1992. Shortly thereafter, Ján left for Canada to play in the Quebec Major Junior Hockey League. Ján was with the QMJHL for three years prior to entering university; he played for, and completed his degree, at Dalhousie University in Halifax. Ján played professional hockey in the ECHL (with the Mississippi Sea Wolves) and spent six seasons in Lubbock, Texas playing for the Cotton Kings. Ján was the all-time high scorer in the franchise’s history.
Ján began coaching hockey while attending and playing at Dalhousie University; he continued coaching youth hockey while playing professionally. Ján is a player agent with EHS, with a focus on youth development.