|Venue: Flushing Meadows, New York Dates: 28 Aug-10 Sept|
|BBC coverage: Live radio and text commentary on selected matches every day.|
Top seed Karolina Pliskova started her bid for a first Grand Slam title with a comfortable win against Poland's Magda Linette in the US Open first round.
The Czech world number one, 25, was not at her fluent best, making 19 unforced errors in a 6-2 6-1 victory.
But ultimately Pliskova - last year's beaten finalist - had too much power for her 72nd-ranked opponent.
She hit eight aces and 29 winners to beat Linette, who has only one US Open win, in one hour and 18 minutes.
"I felt a little bit nervous coming out here, especially after last year. But I think I played pretty solid," Pliskova said.
Meanwhile, defending champion Angelique Kerber lost 6-3 6-1 to Japanese teenager Naomi Osaka.
French Open champion Jelena Ostapenko beat Lara Arruabarrena 6-2 1-6 6-1 in a match which began on court 17 before heavy rain. The final three games were completed under the Arthur Ashe Stadium roof at the end of the day session.
Only three other matches on the outside courts were completed before the rain started after less than two hours' play, causing the cancellation of all matches not scheduled for Ashe, apart from Ostapenko-Arruabarrena.
Belgium's Yanina Wickmayer beat 28th seed Lesia Tsurenko 6-3 6-1, Czech 23rd seed Barbora Strycova defeated Japan's Misaki Doi 6-1 6-3 and Romania's Sorana Cirstea won by the same score against Dutchwoman Lesley Kerkhove.
Pliskova must reach the final to have a chance of retaining her ranking, with six other women all hoping to overtake her by winning at Flushing Meadows.
She has a lot of ranking points to defend after last year's defeat by Angelique Kerber, a fact perhaps contributing to a few nerves before Tuesday's opening match on Arthur Ashe Stadium.
Pliskova moved a break up after both players lost serve in three of the opening four games, then fought off three break points in the seventh game before going on to seal the first set.
After a brief delay when rain forced the roof to be closed, Pliskova broke again in Linette's first service game of the second set and her own dominant serve - despite a brief blip when he she fought off six break points for a 4-1 lead - saw her through.
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