Dejan Zavec (born 13 March 1976), commonly known as Jan Zaveck, is a Slovenian former professional boxer who held the IBF welterweight title. He is the only Slovenian boxer to have held a world title, and in December 2010 was proclaimed Slovenian Sportsperson of the Year.
Dejan Zavec was born in Trdobojci,Slovenia, then part of Yugoslavia. He spent his youth in Gabrnik in the Slovene Hills (Slovene: Slovenske gorice) and in Ptuj. He developed an interest in boxing at an early age. As a teenager, he joined the boxing club in Maribor. Later he resided in Gabrnik and in the city of Magdeburg, Saxony-Anhalt, Germany.
In 2006, he graduated from the Faculty for Physical Education in Novi Sad, Serbia.
On December 11, 2009 Zavec won the IBF welterweight title against South African Isaac Hlatshwayo. On April 9, 2010, Zavec defended the IBF welterweight title for the first time against Rodolfo Martínez in Ljubljana, performing at the Tivoli Hall. He won by technical knockout in the twelfth round when the referee stopped the fight. On September 4, 2010, Zavec defended the IBF welterweight title the second time against Rafał Jackiewicz, performing at the Stožice Arena in Ljubljana. This was the 30th victory in his career. On February 18, 2011, Zavec defended the IBF welterweight title for the third time against Paul Delgado, performing again at the Stožice Arena in Ljubljana, in front of 12,000 spectators. He won with a technical knockout in the fifth round, when the referee stopped the fight.