Two-time ATP Chennai Open winner Marin Cilic of Croatia has pulled out of the season-opening event due to a leg injury, organisers said Wednesday. The world number 21, who won the $450,000 tournament in 2009 and 2010, said in a statement issued by the organisers that a tendon injury will keep him out of South Asia\'s only ATP event from January 2-8. \"Having started the previous five seasons at the Chennai Open, the city is a home away from home for me,\" the left-hander said. \"Thankfully, I am recovering well from the peteller tendon injury and I\'ll surely be back next year.\" Swiss world number 17 Stanislas Wawrinka will defend his title against a strong field that includes world number nine Janko Tipsarevic of Serbia and number 10 Nicolas Almagro of Spain. The 31st-ranked Milos Raonic, a 20-year-old from Canada who was named the ATP\'s newcomer of the year for 2011, will also make his first appearance in Chennai. The tournament on the hard courts of the Nungambakkam Tennis Stadium, serves as a warm-up for the season\'s first Grand Slam, the Australian Open, which starts in Melbourne on January 16.