Karel Pilar was born December 23, 1977 in Prague, Czech Republic. The 3rd choice, 111th overall selection of the Toronto Maple Leafs in the 2001 NHL Entry Draft, Pilar came to North America in 2001-02 after spending the previous season as a member of Litvinov in the Czech Republic.
Known primarily as a stay at home defenseman, Pilar showed some offensive upside with Litvinov in 2000-01 finishing second in team scoring with 38 points. Following a strong season in the Czech Republic, Pilar joined the Leafs AHL affiliate in St. John's where he spent the better part of the 2001-02 season while suiting up for 23 regular season and eleven playoff games with the parent club. Pilar split the first half of the 2002-03 season between Toronto and St. John's, but played only 24 games between the two teams before missing the rest of the season with a virus.
In 2003-04, Pilar suited up for 50 games with Toronto, registering 19 points (2-17-19). He would spend the next two seasons in his native Czech Republic with HC Sparta Praha honing his skills. In 2006-07 he returned to North America and saw action in 10 games with the Toronto Marlies before he signed as a free agent with the Atlanta Thrashers.