The Serbian lost her opening match of the tournament on Monday as she went down 4-6 4-6 to the defending champion.
"I'm definitely very disappointed I made a few easy errors in the last service games of both sets," Ivanovic is quoted as saying by the WTA's official website. "I had a break point at 4-4 [in the first set], which I didn't take and kind of got down a little bit on myself.
"Then I rushed a little bit in the next service game, so that was a little bit disappointing. I felt I created lots of chances, especially off the ground."