Djokovic began his 2021 season by playing for Serbia as the defending champions in the ATP Cup, but the nation was eliminated in the group stage despite Djokovic winning both his singles matches. He then went on to win his 18th Grand Slam title and record-extending 9th title at the Australian Open, with a straight sets victory over Daniil Medvedev in the final. On 1 March, Djokovic equaled Federer's Open Era record of 310 weeks at world No. 1. The following week, he surpassed that mark and has extended the record in his own right. Djokovic skipped the Dubai Open and the Miami masters in order to recover from an abdominal tear he suffered in Melbourne. Djokovic next played at the Monte Carlo Masters, where he defeated the Miami masters runner-up Jannik Sinner in straight sets. However, he ended up losing his third round match to Dan Evans in straight sets. Djokovic then played at the Serbia Open for the first time since 2011 before the tournament was suspended in 2012, defeating Kwon Soon-woo and fellow compatriot Miomir Kecmanović before losing his semifinal match to Aslan Karatsev in three sets. At the Italian Open, Djokovic defeated Stefanos Tsitsipas and Lorenzo Sonego en route to the final, where he lost in three sets to longtime rival Rafael Nadal.