He initially chose swimming but switched to athletics stating that he enjoyed the adrenaline rush in the build up to a race.

In 2008 he was on the verge of quitting athletics but was persuaded to remain by his coach who believed the ruling would be overturned in the future.

He entered his first major international competition that year, representing Poland at the 2013 IPC Athletics World Championships in Lyon.

The 2015 World Championships also saw Derus compete in the long jump, finishing ninth with a distance of 6.24m.

In the finals, he posted a time of 10.79 seconds in a photo finish for the silver medal behind Brazil's Petrúcio Ferreira.