Career
He was drafted in the eighth round, 212th overall, by the Buffalo Sabres in the 1997 National Hockey League Entry Draft. Piroš played six seasons in the Czechoslovakian Extraliga before coming to North America. During that time, Buffalo Sabres traded his National Hockey League rights (along with a fourth-round draft pick) to the Atlanta Thrashers in exchange for Donald Audette.
Piroš joined the Thrashers" American Hockey League affiliate, the Chicago Wolves, in the 2001-2002 season, playing in 64 games and scoring 49 points.
He also made his National Hockey League debut that season with Atlanta, playing in eight games. Over the next two seasons, Piroš would appear in 101 more AHL games with the Wolves and 17 more National Hockey League games with the Thrashers.
In March 2004, Atlanta traded Piroš to the Florida Panthers in exchange for Kyle Rossiter. After finishing the season with the Panthers" organization (playing three National Hockey League games with Florida and 14 games with their AHL affiliate, the San Antonio Rampage), Piroš left for the Russian Super League.
In his National Hockey League career to date, he has appeared in 28 games, recording four goals and adding four assists.
Piroš played two seasons in Russia, one each with Khimik Voskresensk and The Human Context Neftekhimik Nizhnekamsk. In the 2006-2007 season, Piroš joined EV Zug in the Swiss Nationalliga A and left for two seasons with Kölner Haie in German Deutsche Eishockey Liga. In late January 2009, he signed with the Swedish Elitserien club HV71 for the remainder of season 2008-2009.
He left in June 2009 to sign with the Finnish Master of Science-liiga team Ässät Pori, and in late November moved back to Elitserien, this time with Timrå IK.