Samantha Stosur will join fellow Australian Daria Gavrilova in the second round of the Montreal Cup after defeating Brit Heather Watson.

Stosur won in straight sets 7-5 6-3 and will play either Misaki Doi of Japan, or Russian Daria Kasatkina in the second round.

Meanwhile Gavrilova edged German Annika Beck in straight sets, 6-4 6-3 on a wet opening day.

Rain delayed the first set for more than an hour, but Gavrilova returned from the delay stronger than her opponent.

The 22-year-old tweeted about the rain delay after the match, saying “there is a cloud that follows the WTA this year”.

Gavrilova will play Romanian fifth seed Simona Halep in the second round.

The pair have met twice, with the Australian winning the most recent match at the Rome International in May.