NEW YORK: For Kim Clijsters, only when she beats the best will she know her comeback is truly on track.

The former world No 1, back on tour after two years away and the birth of her first child, beat 14th seed Marion Bartoli of France 5-7, 6-1, 6-2 to reach the third round of the US Open, her first grand slam since the 2007 Australian Open.

In her first two events back, the Belgian beat four top-20 players, including French Open champion Svetlana Kuznetsova of Russia.