He holds the school record for career goals (54) and points (144) and was a 1999 NCAA Division III Third Team All American.

He spent three seasons in Portland, his most productive coming in 2005 when he scored thirteen goals in twenty-four games.

In 2007, he led the USL-1 in points, scoring seven goals and adding a league leading nine assists, as the Silverbacks went to the USL-1 championship game.

[7] Antoniuk signed with FC Edmonton of the North American Soccer League (NASL) on March 16, 2011.,[8] scoring four goals and adding four assists for the club .

On October 31, 2003, Antoniuk signed, with the permission of the Portland Timbers, a two-year contract with the Milwaukee Wave of Major Indoor Soccer League (MISL).

The Sockers folded during the 2004–2005 season and the Philadelphia KiXX selected Antoniuk in the first round of the dispersal draft, held January 5, 2005.

[12] On February 20, 2009, he moved to the Chicago Storm of the Xtreme Soccer League, and played 9 games for them during the 2009 XSL season.