Irina-Camelia Begu claimed another big scalp at the WTA Internazionali d'Italia by ending an out-of-sorts Victoria Azarenka's long winning run in the second round on Wednesday.

Former world number one Victoria Azarenka strung together 16 victories in a row before pulling out of the Madrid Open due to a back injury last week, but suffered only her second defeat of the season in Rome.

Fourth seed Azarenka has won three titles this year, but came unstuck in her first match since returning from injury as world number 35 Begu coasted to a 6-3 6-3 win in just an hour and 14 minutes.

Romanian Begu had lost all five of her matches against the world number six, but beat Garbine Muguruza en route to the quarter-finals in Madrid and again showed her prowess on clay at the expense of Azarenka.

The unseeded Begu, who also reached the last eight in the Volvo Car Open last month, broke four times and produced 27 winners to move into the third round in the Eternal City.

It had all started so well for Azarenka, who broke in the first game of the match but then lost four in a row and never recovered as she made 22 unforced errors and coughed up six double faults in a lacklustre display.

Begu pressed home her advantage in the second set, surging into a 5-1 lead with two breaks and moved far more freely than Azarenka as she wrapped up a shock win to set up a meeting with Daria Kasatkina.