But first the No.3-ranked, No.3-seeded Halep had to get past one of the most dangerous unseeded players in the draw this week, Pavlyuchenkova, and it was a battle, particularly in the marathon 63-minute first set, where she rallied from 4-2 down and eventually closed it out in a tie-break.
Halep was actually in the negatives for winners to unforced errors in that first set, 12 to 17, while Pavlyuchenkova was an even 24 to 24 - but the Romanian just kept coming through on the big points.
And once that set was tucked away she ran away with it, racing out to a 3-0 lead in the second set and never looking back, ripping one last backhand winner up the line to close it out, 7-6(3), 6-2.
"I'm really happy that I could win that match and reach the semifinals here for the first time," Halep said. "I really enjoyed this match and played very well. I'm a little bit tired now - I had to run a lot today - but I managed to play aggressive as much as I could, and I just fought for every point out there."
The World No.3 will pass Maria Sharapova for World No.2 on the new rankings if she reaches the final here, which would have major implications at the US Open - the seeds for the last major of the year will be made off those rankings, meaning she wouldn't have to face Serena Williams until the final.
Halep leads Jankovic in their head-to-head series, 5-1. Their first five meetings all went to three sets, but their sixth and most recent meeting in Toronto a week ago was the first straight-setter.
"I played against Halep last week, and I played her in Indian Wells," Jankovic said. "It's different conditions from last week to this week - there it was really windy, and they had different balls. Here it's a little more humid, and the conditions are a little heavier. Every match is really a new match.
"It'll be tough, and hopefully we'll play some really good tennis, but I just need to execute my shots and believe in myself. The most important thing is to believe that I can do it, play well and win."
? WTA (@WTA) August 22, 2015