Ivan Ljubicic announces retirement - Tennis - Sport - The Independent Former world number three Ivan Ljubicic has announced he will retire from tennis next month following the Monte-Carlo Rolex Masters. The Croatian, who turns 33 this month, was a fixture in the top 10 between 2005 and 2007, reaching his career high in August 2006, the same year he made the semi-finals at the French Open, his best grand slam performance. Ljubicic helped Croatia win the Davis Cup in 2005 and won 10 ATP World Tour titles, with his biggest coming in surprising fashion at the Indian Wells Masters in 2010, when he beat both Novak Djokovic and Rafael Nadal. Explaining his decision, the world number 40 said on http://www.atpworldtour.com: "It's never an easy decision for any professional athlete to retire. I look forward to the next stage of my life. Tennis has given me so much and I want to continue to stay involved and contribute in some ways. Ljubicic has been involved in the administrative side of the sport since 2002, serving on the Player Council until 2008 when he was elected onto the board of directors. Roger Federer paid tribute to Ljubicic, saying: "He's been a wonderful friend to me on tour, and he's also been very beneficial to the game of tennis, not just on the court but off the court because he's been part of the political system here. He has a great future ahead in tennis or whatever he wants to do, because he's a bright man and he's a great person. It's sad seeing him go, but he's had a wonderful career and I can only congratulate him for that.