Defending champion Dominic Thiem has pulled out of the US Open and will miss the rest of the year because of a wrist injury. Thiem, 27, was hurt in June while playing in the Mallorca Open and said the pain returned last week after he hit a ball during training. Doctors recommended he wear a wrist splint for another six weeks before resuming training. This is the second straight year that the defending champion at Flushing Meadows has withdrawn from the event after Rafa Nadal skipped the 2020 edition due to concerns over the coronavirus. Thiem came back from two sets down <a href="https://www.thenationalnews.com/sport/tennis/dominic-thiem-wins-elusive-first-grand-slam-at-us-open-in-pictures-1.1077281" target="_blank">to beat Alexander Zverev 2-6, 4-6, 6-4, 6-3, 7-6</a> in a thrilling battle in New York last September. “Unfortunately, I've had to withdraw from the US Open and will miss the rest of the 2021 season,” he posted on Twitter. “I'm really disappointed not to be able to defend the title in New York but I haven't recovered from the wrist injury I suffered back in June at the Mallorca Open. “The past six weeks, I've been following medical advice, wearing the wrist splint, doing exercise to stay in shape before starting to train back on the courts. “My recovery was going really well but then last week I hit a ball during training and started to feel some pain again. I went straight to see the doctors. “After some tests, they said that my wrist needs more time, so we've agreed on being conservative and to give my wrist some time to recover. I'll wear the wrist splint for a couple more weeks before starting with exercises and then training with the racquet again. “It has been a tough decision but I know this is what I have to do. I have a long career ahead of me nd it's important not to take risks and rush back.” On Sunday, another former champion Roger Federer also pulled out of the US Open. The 40-year-old, who has five US Open titles to his name, said he needed further knee surgery and admitted he “will be out for many months". The other two members of the “Big Three”, Nadal and Novak Djokovic, are both absent from the ongoing Masters tournament in Cincinnati which traditionally serves as a dress rehearsal before the US Open. The 35-year-old Nadal has been suffering from a left foot injury since his <a href="https://www.thenationalnews.com/sport/tennis/djokovic-stuns-king-of-clay-nadal-to-reach-french-open-final-1.1239512" target="_blank">semi-final exit at the hands of Djokovic at the French Open</a> in June. The Serb, meanwhile, who has won all three majors this season and is eager to make a clean sweep in New York, has not taken to the court since the Tokyo Olympics, which he left mentally and physically exhausted after his losses in the semi-final and in the bronze medal match.