Zurich, June 10 : Swiss legend Roger Federer on Wednesday announced that he will be out of action for the rest of the 2020 season after undergoing another arthroscopic surgery on his right knee. In a tweet, Federer said that he expects to be back in action at the start of 2021. "Dear fans, I hope you are staying safe and healthy. A few weeks ago, having experienced a setback during my initial rehabilitation, I had to have an additional quick athroscopic procedure on my right knee," Federer said in his statement. "Now, much like I did leading up to the 2017 season, I plan to take the necessary time to be 100 % ready to play at my highest level. I will be missing my fans and the tour dearly but I will look forward to seeing everyone back on tour at the start of the 2021 season. All the best, Roger," he added. The 20-time Grand Slam champion last participated in the Australian Open where he lost to Novak Djokovic in the semi-finals earlier this year. No other grand slam has taken place this year as all tennis matches and tournaments have been suspended following the outbreak of novel coronavirus. This will be the longest duration the 38-year-old would be away from the tour since making his debut in 1998. He had missed the entire second half of 2016 due to injury before returning to win the Australian Open and Wimbledon in 2017. Recently, Federer had become the first from tennis to top Forbes' list of highest paid athletes. With an estimated $106.3 million earned over the past 12 months, he edged out Portuguese football superstar Cristiano Ronaldo from the top spot. /IANS