Ivan Klasnić is a Croatian former professional footballer who played as a striker.
He began his career with local side St. Pauli, and moved to Werder Bremen in 2001 after helping his previous team to promotion to the Bundesliga. He scored 49 league goals in 151 appearances with Werder Bremen, winning a league and cup double in 2004. After a season in France with Nantes, he moved to English Premier League team Bolton Wanderers in 2009, initially on loan. After their relegation in 2012, he spent a season back in Germany with Mainz.
Klasnić played also for the Croatian national football team. In 2007, Klasnić underwent a kidney transplant, and became the first player to participate in a major tournament (UEFA Euro 2008) after a transplant. He also represented Croatia at UEFA Euro 2004 and the 2006 FIFA World Cup.