BERLIN: NBA star Dirk Nowitzki says he could retire as early as next year, but admits his dream is to play until 2018 and celebrate 20 years with the Dallas Mavericks. Nowitzki has played for the Mavericks since joining from DJK Wurzburg in 1998. The German was the NBA Finals’ MVP during the team’s 2011 championship year and is a 13-time NBA All-Star, but at 38-year-old is coming to the end of his career. “If things don’t go so well and it hurts everywhere, it could be that 2017 will be the end,” the forward told German magazine Sport Bild. “Actually, my plan is to complete the 20 years and play for Dallas until 2018. Nowitzki is currently struggling with a persistent Achilles tendon problem, has not played since November 25 and says he wants to speak to Mavericks’ bosses next summer about his future.