Former champion Venus Williams set up a US Open fourth-round showdown with Kim Clijsters by defeating Magdalena Rybarikova of Slovakia 6-2, 7-5. Clijsters , who is on the comeback trail after taking two years out of the sport to marry and have a baby, earlier defeated fellow Belgian Kirsten Flipkens 6-0, 6-2. The two played 10 times before Clijsters walked away from tennis in May of 2007, with Williams leading 6-4. But it was Clijsters who won their last meeting 4-6, 7-5, 6-1 in a quarter-final tie here in 2005 en route to her only Grand Slam title win.