The Romanian's 2011 season ended with three very successful tournaments. She reached the fourth round of the US Open, her best grand slam result to date, before losing to eventual semifinalist Angelique Kerber. She then upset French Open champion Li Na 6-4, 6-0 in the first round of the China Open in Beijing and reached the semifinals at the WTA Premier event.

In her final tournament of the year, she reached her first WTA final at the BGL Luxembourg Open, where she lost to #2 Victoria Azarenka.

Monica ended the year ranked #30 in the world, her best year-end ranking.