Career
Leko started his career with his hometown club Hajduk Split and played there for several seasons before moving to Spain to join Málaga CF. In his early senior years, he was loaned to HNK Trogir. In January 2005, Leko returned for a brief stint with Hajduk. In the summer he joined Club Brugge.
On 15 January 2009, he decided to sign a contract for K.F.C. Germinal Beerschot.
After his spell at the Antwerp side, he went on with his career at K.S.C. Lokeren. Leko made 13 appearances for the Croatia national football team, and was called up to the squad to participate in the 2006 World Cup, but played no part in the tournament, as Croatia exited in the group stage.
Hajduk Split
Prva HNL: 2000-2001, 2004-2005
Croatian Cup: 1999–2000
Málaga
Union of European Football Associations Intertoto Cup: 2002
Club Brugge
Belgian Cup: 2006-2007
Belgian Supercup: 2005
Lokeren
Belgian Cup: 2011-2012.