Rafael Nadal said on Wednesday he is still not satisfied with his 21 Grand Slam titles following his historic triumph at the Australian Open. Nadal clinched his latest major win in Melbourne after pulling off an incredible comeback from two sets down to defeat Russia’s Daniil Medvedev in the final. The 35-year-old’s momentous victory took him to the top of the all-time men’s list and one clear of the 20 Grand Slam titles won by Roger Federer, who is injured, and Novak Djokovic, who was controversially deported from Australia before the tournament began. The Spaniard could now make it 22 at the…