Following the first game of the new season, in which he bagged two goals against Ružomberok, Halenár transferred to Artmedia for an undisclosed fee, reported to be in the region of 20 million Slovak crowns.
[1] In only his second game for Artmedia on 27 July 2005, he scored a hat-trick against Celtic Glasgow in the 2005 UEFA Champions League second qualifying round tie.
[5] In January 2015, Halenár left the Slovak league and signed for Hungarian team Nyíregyháza Spartacus, where he stayed until the end of the season.
On 13 November 2007, he made his debut for Slovakia's senior team in a qualifying game for the 2008 European Championship against the Czech Republic.
On 30 June 2018, just two days after his 35th birthday, Halenár was found dead in the woods of Vrakuňa outside the Slovak capital of Bratislava.