|Born||October 10, 1985
|Height||6 ft 0 in (183 cm)|
|Weight||214 lb (97 kg; 15 st 4 lb)|
New Jersey Devils
HC Sparta Praha
|National team||Czech Republic|
|NHL Draft||7th overall, 2004
He was drafted by the Florida Panthers with the 7th overall pick in the 2004 NHL Entry Draft. He also played in the NHL for the Florida Panthers for 6 seasons. He was traded by the Florida Panthers to the Chicago Blackhawks for defenceman Brian Campbell on June 24, 2011.
He played 6 games with the Blackhawks and played a season with their AHL farm team, the Rockford IceHogs. On July 5, 2013, Olesz signed a 1 year deal with the New Jersey Devils. On November 21, 2013, he signed a contract with SC Bern of the NLA.