Tennis-French Open day six

PARIS (Reuters) - Highlights of the sixth day at the French Open, the second Grand Slam of the year, on Friday (all times GMT).

Fifth seed Stefanos Tsitsipas was handed his first real test at this year's French Open before he subdued big-serving American John Isner 5-7 6-3 7-6(3) 6-1 to move into the fourth round.

The 22-year-old, who won two titles on clay in the run-up to Roland Garros, had to endure a torrid serving barrage in the opening set but eventually found his stride to set up a fourth round clash with Spanish 12th seed Pablo Carreno Busta.

Russian Daniil Medvedev firmly put his dislike for clay behind him during a commanding 6-4 6-2 6-4 win against towering American Reilly Opelka.

The rangy 25-year-old, who had never won a match at the claycourt Grand Slam in four previous appearances, stayed on course to clinch the world number one ranking.

In the women's draw, seventh seed Serena Williams powered to a 6-4 6-4 win over fellow American Danielle Collins as the field opened up enticingly.

The 39-year-old Williams, the highest ranked player left in the bottom half of the draw, is chasing a record-equalling 24th Grand Slam singles title and will next play Kazakhstan's 21st seed Elena Rybakina for a place in the quarter-finals.

1610 SERENA WILLIAMS ADVANCES TO LAST-16

Serena Williams overcame a minor blip to beat American compatriot Danielle Collins 6-4 6-4 to move into the last-16.

Down 4-1 in the second set, 39-year-old Williams won five games in a row to seal a straight-sets win.

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1545 MEDVEDEV MARCHES INTO LAST-16

On his least favourite surface, second seed Daniil Medvedev was impressive once again as he struck 28 winners in a 6-4 6-2 6-4 victory over American Reilly Opelka. The 25-year-old Russian reached the last-16 at Roland Garros for the first time in five appearances.

1400 ZVEREV FIGHTS BACK TO DISPATCH DJERE

German sixth seed Alexander Zverev beat Laslo Djere 6-2 7-5 6-2 after a remarkable comeback in the second set to set up a last-16 clash with Kei Nishikori.

Zverev found himself 5-2 down in the second set when he roared back into form to win five games in a row.

1338 DELBONIS OUSTS FOGNINI IN STRAIGHT SETS

Argentine Federico Delbonis advanced to the fourth round of a Grand Slam for the first time in his career after a 6-4 6-1 6-3 win over Italian 27th seed Fabio Fognini, who made 53 unforced errors.

1315 NISHIKORI THROUGH AS PLAY RESUMES ON OUTER COURTS

Play resumed at Roland Garros on outer courts following a short rain delay. Japan's Kei Nishikori has progressed to the last-16 after his opponent Henri Laaksonen of Switzerland retired hurt, trailing 7-5.

1215 RAIN HALTS PLAY ON OUTER COURTS

Play was suspended on the outer courts at Roland Garros due to rain. Sixth seed Alexander Zverev's third round match against Serbia's Laslo Djere will continue under the roof on Court Philippe Chatrier.

1145 AZARENKA ADVANCES

Two-times Grand Slam winner Victoria Azarenka produced a clinical display to dispatch American Madison Keys 6-2 6-2 and book a place in the last-16 at Roland Garros for the first time since 2013.

1050 SABALENKA OUSTED BY PAVLYUCHENKOVA

Third seed Aryna Sabalenka was knocked out in the third round by Russia's Anastasia Pavlyuchenkova, who took revenge for her semi-final loss in Madrid last month with a 6-4 2-6 6-0 victory on Court Simonne Mathieu.

Sabalenka's exit early in the Grand Slam means fourth seed Sofia Kenin is now the highest seed in the women's draw after Ash Barty (injury) and Naomi Osaka (withdrawal) also bowed out.

1011 RYBAKINA MOVES INTO FOURTH ROUND

Kazakh Elena Rybakina sealed a 6-1 6-4 victory over Russia's Elena Vesnina on Court Suzanne-Lenglen in a match that lasted one hour and three minutes.

0909 PLAY UNDER WAY

Play began in cloudy conditions at Roland Garros, with the temperature hovering around 18 degrees Celsius (64.4°F).

(Reporting by Manasi Pathak, Rohith Nair and Hardik Vyas in Bengaluru; Editing by Toby Davis)