Billirakis won the first tournament of the 2007 World Series of Poker winning the $5,000 World Championship Mixed Hold'em Limit/No-Limit event after beating Canadian poker player and former professional hockey player Greg Mueller heads-up.

Billirakis' record was broken on September 10, 2007 when Annette Obrestad won the main event of the World Series of Poker Europe where the age limit was only 18 years.

[3] On one key hand when they were heads up, Mueller had made top pair against Billirakis's trips.

While not a formal breach of the rules, ESPN commentator Norman Chad opined that such plays "ain't kosher" according to poker etiquette.

In November 2008, Billirakis won a WSOP Circuit Event - Horseshoe Hammond, $5,150 Championship, earning $208,885.