Eduardo Avelar was always an athletic child, spending hours playing soccer, skateboarding, and training judo. This last one would eventually lead him to Brazilian jiu-jitsu, which was being offered at the same gym. It soon became clear that this was a perfect match and the young Avelar changed his focus to strictly grappling.

He competed inside his home state of Rio de Janeiro until he was 16, when he decided to test his mettle in the wider world. At 17 years old he took his first international victory at the European International Open in Portugal as a blue belt. That win carried him on to even greater victories in his professional career.