The Canadian made short work of Patricia Mayr-Achleitner, defeating her Austrian opponent 6-4 6-1 to set up a last-16 encounter with Tsvetana Pironkova.

As the top seed for the WTA International hard-court event, Bouchard will fancy her chances of winning her second WTA singles title of the year after Ana Ivanovic, Dominika Cibulkova and Sabine Lisicki all bowed out.

The trio followed the likes of Andrea Petkovic, Barbora Zahlavova-Strycova and Caroline Garcia in exiting the tournament, meaning Bouchard and Karolina Pliskova are the only seeds left.

Second seed and 2010 champion Ivanovic pulled out of her match against Madison Brengle with a hip injury, while third and fifth seeds Cibulkova and Lisicki lost to Anna-Lena Friedsam and Karin Knapp respectively.

After a topsy-turvy first set in which Bouchard got just 34 per cent of her first serves in, the world number six dominated the second, lifting that mark to 72 per cent and breaking her opponent three times in succession on her way to victory.

Cibulkova, runner-up to Petra Kvitova here three years ago, looked to have things under control when she took the first set against German qualifier Friedsam.

But Friedsam hit back, sending down seven aces to Cibulkova's none and eventually closing out the 2-6 6-3 6-4 win on her fourth match point.

Lisicki began strongly, breaking Knapp in the very first game, but the Italian hit back to level at 4-4 before a second break in game 12 saw her take the first set.

World number 25 Lisicki looked to have found some form in the second as she reeled off five consecutive games from 2-1 down to force a decider, but Knapp dominated the final set tie-break to prevail 7-5 2-6 7-6 (7-1).

Marina Erakovic defeated Klara Koukalova 6-0 6-2 in her second-round match, and will now take on Camila Giorgi in the quarter-finals after the Italian overcame Tunisian qualifier Ons Jabeur 6-3 6-2.

Elsewhere, Stefanie Voegele will join them in the last eight after coming from a set down to see off Anna Schmiedlova 2-6 6-1 6-4.