Melbourne:Venus Williams is out in the fourth round of the Australian Open while the Russian revolution also suffered big casualties. Venus was knocked out by Australian Alicia Molik in straight sets in the fourth round of the Australian Open today. The other upset of the day saw French Open champion Anastasia Myskina knocked out by Nathalie Dechy. Myskina had an embarrassing number of unforced errors â€“ a total of 45. Not surprisingly, she lost to Frenchwoman Nathalie Dechy who now plays Patty Schnyder of Switzerland. The 12th-seeded Schnyder got through after 61 unforced errors from Elena Dementieva. The Russian who was runner up at two grand slams last year had won the first set and was leading 4-0 in the second. But ten double faults meant that her notoriously weak serve was again to blame. In the men's draw Lleyton Hewitt had to claw his way back from two sets down to advance to his first quarter final in Melbourne. The Australian down two sets to one used the crowd support to his advantage winning 7-5, 3-6, 1-6, 7-6, 6-2 in three hours and 53 minutes. Meanwhile Andy Roddick, who has dropped just one set so far in the tournament had an easy 6-3, 7-6, 6-1 win over Germany qualifier Philipp Kohlschreiber.