Career
He collected a total of three medals (two golds and one bronze) in the 50, 100, and 200 m freestyle at the 2004 European Junior Swimming Championships in Lisbon, Portugal. Gasior qualified for two swimming events at the 2008 Summer Olympics in Beijing, by clearing a FINA B-standard entry time of 1:48.52 (200 m freestyle) from the European Championships in Eindhoven, Netherlands. In the 200 m freestyle, Gasior challenged seven other swimmers on the eighth and final heat, including top medal contenders Dominik Meichtry of Switzerland, Michael Phelps of the United States, and Park Tae-Hwan of South of Korea.
Gasior rounded out the field in last place by three seconds behind top qualifiers Meichtry and Phelps with a time of 1:49.25.
Gasior failed to advance into the semifinals, as he placed thirty-fourth overall in the preliminary heats. He also teamed up with Łukasz Wójt, Michał Rokicki, and Przemysław Stańczyk in the 4 × 200 m freestyle relay.
Swimming the lead-off leg, Gasior recorded a split of 1:48.40, and the Polish team went on to finish heat two in seventh place and fourteenth overall with a final time of 7:18.09.
