Career
He represented Slovenia at the 2010 Fédération internationale de football association World Cup. He was directly responsible in Slovenia"s successful qualification to the 2010 World Cup, as he was the scorer of a crucial goal against Russia in the 2010 World Cup qualification playoffs. Pečnik"s older brother, Andrej, is also a professional football player.
Celje
After showing promise in its youth teams he was signed by NK Celje, making his first division debut on 24 April 2004 against Football Club Ljubljana.
The following year Pečnik played in only seven league matches, adding a few Cup appearances including the final against Football Club Koper. In the 2005-2006 season he managed to gain a regular place in the first team, eventually establishing himself as a key offensive player.
In 2007-2008, Pečnik was Celje"s top scorer with 14 league goals. After five seasons he was loaned out in June 2008 to Sparta Prague, but appeared rarely with the Czechoslovakian first division outfit during his six-month stay, spending most of his time with the reserve squad.
Nacional
After a further 15 league games with Celje, Pečnik signed with Communicative Disorders Nacional of Portugal.
On 16 July 2012, after three seasons of irregular playing time, also being loaned to Russian club Football Club Krylia Sovetov Samara for five months, he signed a two-year deal with Sheffield Wednesday in the Football League Championship. Sheffield Wednesday
In his official debut with the Owls, on 12 August 2012, Pečnik missed a penalty and was booked before half-time, as his team trailed at Oldham Athletic 0–2. Pečnik was released by Wednesday at the end of his only campaign.
Red Star Belgrade
Pečnik agreed to a two-year contract with Red Star Belgrade from Serbia, on 1 July 2013.
He scored his first goal for Red Star against ÍBV in the second qualifying round of the 2013-2014 Union of European Football Associations Europa League.