Venus Williams was made to sweat before prevailing past world number 193 Rebecca Marino on day three of the US Open.
Top seeds come through unscathed in New York
Two-time champion Venus Williams was made to sweat before prevailing past world number 193 Rebecca Marino on day three of the US Open.
The number three seed unleashed a huge sigh of relief after seeing off her Canadian counterpart 7-6 (7-3) 6-3 on Arthur Ashe.
Williams was one of a host of female seeds to come through unscathed in searing temperatures in New York.
French Open champion and number six seed Francesca Schiavone, No.12 seed Elena Dementieva and No.24 seed Daniela Hantuchova also claimed impressive victories.
But it was Williams, who triumphed in New York in 2000 and 2001, who was expected to have the least trouble reaching the third round.
19-year-old Marino, who had not won a single game on tour before beating Ksenia Pervak in round one, had other ideas though and held serve all the way through the opening set.
Demolition
The plucky Canadian also claimed a mini-break in the tie-breaker to enhance hopes of a shock victory, but Venus slammed the door firmly shut by reeling off six points in a row to take the set.
Marino fought gamely in the second set but, after relinquishing serve in the fourth game, there was no way back, and Venus served out a hard-fought win to set-up a third round showdown with another qualifer, Mandy Minella.
Italian Schiavone had no such trouble, the Frenchwoman following up her 6-1 6-0 victory over Ayumi Morita in round one with an equally comprehensive win.
This time it was compatriot Maria Elena Camerin who was put to the sword following a 6-2 6-1 demolition.
Russian Dementieva also remains on track, the 2004 runner-up fighting hard in the second set to see off Austrian Sybille Bammer 6-3 6-4 on Court 11.
Dementieva's reward is a third round encounter with Hantuchova - a 5-7 6-3 6-4 victor over American Vania King on Louis Armstrong Stadium.
