Eating grass to celebrate his Wimbledon title is becoming a habit for Novak Djokovic and the Serb engaged in his customary act again on Sunday after beating Matteo Berrettini of Italy in the final in four sets.Soon after securing a 6-7(4), 6-4, 6-4, 6-3 victory, Djokovic plucked some grass from the Centre Court surface and chewed on it -- something he has done after each of his five previous triumphs here.He first did this in 2011 after beating Rafael Nadal for his first Wimbledon title.Djokovic had once explained why he celebrates in this manner at Wimbledon."When I was younger, I always dreamt of winning Wimbledon and I wanted to do something different. And I didn't come up with a more original idea, so I thought I might as well just eat some grass," Djokovic had said.He once again referred to his childhood dream during the prize distribution ceremony on Sunday."A seven year old boy preparing Wimbledon trophy with improvised material in his room, and today standing here with my sixth Wimbledon trophy, it's incredible," he said on Sunday.