Mario Ančić started tennis at the age of seven and turned pro in 2001. He first caused a stir in 2002 when he defeated Roger Federer in the first round of Wimbledon , for whom it was the last defeat on grass until the Wimbledon final in 2008.
In 2003, Ančić surprisingly reached the round of 16 at the Australian Open . In the same year he had the strongest player of the season at the French Open at the time, Andre Agassi , on the verge of defeat, but despite a 2-0 set lead he was defeated just 5: 7 in the fifth set.
In 2004 he reached the final of an ATP tournament for the first time in his career at the tournament in Milan , where he was defeated by Antony Dupuis from France 6-7 in the third set. He also reached the semi-finals of Wimbledon this year by defeating the British Tim Henman very clearly in the quarter-finals. In the semifinals, however, he lost to Andy Roddick in four very close sets. In addition, Ančić won bronze in doubles with Ivan Ljubičić at the Olympic Games .
In 2005 Ančić was able to win a tournament for the first time in Den Bosch when he defeated the doubles specialist Michaël Llodra in the finals of the grass tournament . He also reached the final of the Scottsdale and Tokyo tournaments in 2005 , but lost there to his supposedly weaker opponents Wayne Arthurs and Wesley Moodie . In December 2005 Ančić won the Davis Cup with Croatia and played an important role because he defeated Michal Mertiňák from Slovakia in the decisive match .
In 2006 Ančić immediately reached the final in a preparatory tournament for the Australian Open in Auckland after a sovereign tournament course, but lost to Jarkko Nieminen from Finland . In February he also reached the final in Marseille , but lost to Arnaud Clément from France . In May Ančić won the unofficial world championship title with Croatia in Düsseldorf at the Arag World Team Cup with a final victory against Germany. In addition, he reached the quarter-finals at the French Open and Wimbledon that year and narrowly missed qualifying for the Masters Cup. At the Australian Open 2007 he was eliminated after an exciting and very open match after five sets (3: 6, 6: 3, 1: 6, 7: 5 and 4: 6) against Andy Roddick in the round of 16.
He canceled the Australian Open 2008 due to an injury. After a very long injury break, he returned to the tennis court at the tournament in Marseille . Right away he reached the final, in which he was defeated by the British Andy Murray . On the way to the final, he defeated Marcos Baghdatis and also the local hero and Australian Open finalist 2008, Jo-Wilfried Tsonga . At Wimbledon he reached the quarter-finals, where he was then defeated by the five-time tournament winner and world number one Roger Federer .
Ančić's highest placements in the world rankings were 7th in singles and 47th in doubles.
On February 22, 2011, Ančić announced his retirement from active tennis due to persistent injuries and back pain.