Sharapova trailed Bartoli 4-0 in the opening set yesterday evening when rain forced the match to be abandoned.
When the duo returned to the Arthur Ashe Stadium today, Sharapova responded positively to book her place in the semi-finals at Flushing Meadows for the first time since 2006.
"The rain break gave me a few hours to think about things. I came out so flat yesterday. She's so tough and she was on fire," she told reporters. "I'm so happy to get back to the semi-finals."
Sharapova will now take on world number one Victoria Azarenka.