Following a standout junior career in the second-tier Russian Hockey Super League Nik Antropov was selected in the first round, 10th overall by the Toronto Maple Leafs in the 1998 NHL Entry Draft. He managed to appear in over 70 games in only two of his nine seasons with the Leafs. However, his time in Toronto was not without its successes, for much of his time in the blue and white he rode shotgun for Maple Leafs all-time leading scorer, Mats Sundin and began to establish himself as a bonafide front-line NHL forward. In the summer of 2009, Antropov was traded by the Maple Leafs to the New York Rangers In return the Maple Leafs acquired a second-round draft pick. On July 2, 2009 Antropov signed a four-year deal with the Atlanta Thrashers as a free agent, there Antropov would establish a new career-high in points during his first year in Atlanta. In 76 games, he scored 24 times and added 43 assists for 67 points. The Thrashers would relocate to Winnipeg prior to the 2011-12 season and were renamed the Jets. On October 9, 2011, it was Antropov who scored the first goal in Winnipeg Jets franchise history.
After two seasons in Winnipeg, Nik Antropov signed as a free agent with Barys Astana of the KHL. He would spend two years with the club before officially announcing his retirement from professional hockey.