Heather Watson claims the scalp of Monica Niculescu in Quebec

Heather Watson upset fourth seed Monica Niculescu to reach the second round of the Coupe Banque Nationale.

The British No 2, who lost in the first round at the US Open, secured a 7-5, 6-3 win over the Romanian in two hours and 19 minutes.

After a pretty even opening set that lasted 80 minutes, Watson threatened to bagel Niculescu in the second set as she raced into a 5-0 lead, but her opponent put up a fight and won the next three games before the world No 107 served it out.

Watson will face Leylah Fernandez next after the Canadian wildcard beat her compatriot Gabriela Dabrowski 6-3, 7-5.

Third seed Monica Puig also had a comfortable day at the office as the defending Olympic champion beat Beatriz Haddad Maia from Brazil 6-2, 6-3.

She will take on Madison Brengle in the second round after the American qualifier beat Victoria Duval 6-4, 6-7 (2-7), 6-4.

Eighth seed Pauline Parmentier defeated Veronika Kudermetova 7-5, 6-3 while Christina McHale came out on top in a marathon match against Dayana Yastremska, winning 2-6, 6-2, 7-6, (7-1).

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