Injury and poor form has seen Ivanovic slip to 62nd in the rankings
Ana Ivanovic will meet Kim Clijsters in the Cincinnati Open semi-finals after ending the run of Akgul Amanmuradova.
Serbia's former world number one eased past the unseeded Uzbekistan player 6-1 6-3, while Clijsters beat Flavia Pennetta of Italy 7-6 (8-6) 6-4.
The other semi-final will feature Maria Sharapova against fellow Russian Anastasia Pavlyuchenkova.
Sharapova saw off Marion Bartoli of France 6-1 6-4, while Pavlyuchenkova beat Yanina Wickmayer 7-5 3-6 6-1.
Ivanovic continued her recovery from a rankings slump which left her unseeded by reaching her second semi-final of the year.
She won 22 of 24 first service points and looked composed throughout as she overcame Amanmuradova, who beat defending champion Jelena Jankovic in the quarter-finals.
"I think it has to do with confidence. You know, once you feel confident that you've got a game out there and you've got tools, you can fall back on those," she said.
"At the moment, I feel if my forehand isn't working, I can fall back on something else, if that's not working I can fall back on my movement and just trying to get to the balls and somehow get them back."
Clijsters, who is preparing to defend her US Open crown later this month, was pushed all the way by 11th seed Pennetta.
The Belgian, who launched her comeback from retirement at this event last year, made 39 unforced errors and conceded she was not at her best.
"The errors are there because I still don't feel that everything is going naturally the way that I would want it to go. I'm really just trying to work for each point," she said.
Sharapova was rarely troubled in her defeat of France's Marion Bartoli, with the former world number one producing a blistering service game, winning 29 of 30 first serve points and hitting nine aces.
The three-time Grand Slam winner is likely to face a tougher time of it in her semi-final after Pavlyuchenkova ended the hopes of Belgian 12th seed Wickmayer.
She was 5-1 down in the first set but saved three set points to rally back superbly, winning six successive games.
Wickmayer, who later said she had felt weak in her legs and drained by the midday heat, called for the courtside trainer when she was 6-5 down.
There was an almost identical start to the second with Wickmayer going 5-0 up before Pavlyuchenkova again battled back, though the Belgian forced it into a third set.
But the 19-year-old Russian swept her aside in the decider to set up a clash with Sharapova.
"I started off really well in the first set, got really tired after that and she came back and put up a great fight," Wickmayer said.