The world number seven responded emphatically to Monday's defeat to defending champion Serena Williams in Singapore by securing a first career victory over Canadian Bouchard and a 57th success of the season, thanks to a 6-1 6-3 triumph.

With her left thigh heavily strapped, Bouchard slumped to a second successive straight-sets defeat and heads into her final Red Group round-robin against Williams needing an emphatic win to have any chance of making the semi-finals.

Debutant Bouchard arrived at the season-ending tournament having withdrawn injured from the Generali Ladies Linz earlier this month.

And major doubts remain over her match fitness after an indifferent display at the Singapore Sports Hub as she made 31 unforced errors.

Bouchard passed on two crucial break points that would have prolonged a one-sided opening set, in both the first game as well as the seventh and final game.

Ivanovic was visibly more sprightly around the court and duly raced into a 5-0 lead as a result.

Serving to avoid a bagel, Bouchard finally got on the scoreboard, flinging her arms up in a combination of frustration and mock celebration when Ivanovic hit long.

However, Ivanovic overcame a brief scare to serve out the first set and immediately continued her momentum into the second as Bouchard was broken at the second attempt in the opening game.

Then came Bouchard's only break of the match to level at 1-1 as the Canadian finally posed Ivanovic problems.

An epic seventh game at 3-3 saw Bouchard battle brilliantly to hold serve five times before a double fault proved costly and Ivanovic went 4-3 up at the sixth time of asking.

Bouchard missed a golden opportunity to break back immediately as she advanced rapidly to scoop long.

And the Serb quickly punished the 20-year-old to edge 5-3 ahead and then clinch the victory, much to her delight following her Williams setback earlier this week.

"No matter what, I tried to come out and enjoy the match," said the 2008 French Open champion, who finishes her group campaign against Simona Halep

"I tried to be aggressive and I'm very pleased. The seventh game [in the second set] was huge, but I was very happy to get that game."