At the Australian Open Grand Slam tennis tournament in Melbourne today, women's title favourite Serena Williams and men's defending champion Novak Djokovic entered the second round of the singles competition. Williams kicked off her bid for an 18th grand slam title with a 6-2 6-1 demolition of local wildcard Ashleigh Barty.In the Men's singles, aiming for a fourth successive title at Melbourne Park, Serbia's Novak Djokovic defeated Lukas Lacko of Slovakia in 6-3 7-6 6-1 to reach the second round.Indian Number One Somdev Devvarman will meet 26th seeded Spaniard Feliciano Loez in the opening round of the Men's Singles at the Australian Open tomorrow. In the first round upsets in the women's singles, Thai world number 88 Luksika Kumkhum bundled out sixth seed Petra Kvitova 6-2 1-6 6-4. Venus Williams became another major casualty when she threw away a one-set lead against Russian 22nd seed Ekaterina Makarova to slump to her worst Australian Open result since 2006. The seven-time Grand Slam champion lost 6-2, 4-6, 4-6. However, China's Li Na advanced to the second round defeating last year's girls' champion Ana Konjuh, 1-6, 6-2, 6-0.