Paris: Top seed Serena Williams got the better of Magdalena Rybarikova, 6-2, 6-0, to advance into the second round of the French Open, here on Tuesday.

On a day of upsets, which saw No.3 and No.5 seeds Angelique Kerber and Victoria Azarenka being ousted earlier in the day, Williams won the match in 44 minutes, striking 25 winners to just five unforced errors, and breaking serve six times to set up a second round encounter with Teliana Pereira, who ended the day with a titanic 7-5, 3-6, 9-7 win over Kristyna Pliskova.

Meanwhile, Karin Knapp defeated Victoria Azarenka, 6-3, 6-7(6), 4-0 ret. No.9 seed Venus Williams got a scare twice by a surging Anett Kontaveit, but the seven-time Grand Slam winner edged past her 7-6(5), 7-6(4) for a spot in the second round.

Meanwhile, Kiki Bertens caused the first major upset at this year's French Open, knocking out No.3 seed Angelique Kerber 6-2, 3-6, 6-3 in the first round on Tuesday.

Nadal at his best

Rafael Nadal began his 2016 Roland Garros campaign with ease as he breezed past Australian Sam Groth 6-1, 6-1, 6-1 in an hour and 20 minutes to move into the second round. The Spaniard lost only five points on his serve (40/45), landed 84 per cent of his first serves and hit 25 winners to three unforced errors.

In the second round, Nadal will face Argentine Facundo Bagnis, who beat Frenchman Kenny De Schepper in three sets.

Meanwhile, Dominic Thiem matched his best performance at Roland Garros by reaching the second round. Thiem, who defended his title at the Open de Nice Cote d’Azur on Saturday, dismissed Spaniard Inigo Cervantes 3-6, 6-2, 7-5, 6-1.

John Isner prevailed against Australian John Millman, who was making his Roland Garros debut, 6-7(4), 7-6(12), 7-6(7), 7-5.