Pavlyuchenkova, who had taken out No.7 seed Carla Suárez Navarro and No.4 seed Angelique Kerber in the last two rounds, rallied from a set down and an early break in the third to beat the No.1-seeded Sharapova, 46 63 64. Sharapova hit back-to-back double faults on the last two points of the match.
"I'm very happy with my performance today," Pavlyuchenkova said. "Maria's so tough and she's always fighting until the end, so I'm happy I stuck with my game and kept fighting out there as well.
"I had to serve well - I had no choice today, because Maria has one of the best returns on the tour. We played a few years ago and she broke me a lot of times so that was a key for her to win again today, and I just tried to serve the best I could today. It was working well, so I'm very happy with it."
Pavlyuchenkova is now one win away from the biggest title of her career. She has only been to one Premier-level final before, at Brisbane last year - falling to Serena Williams. She is 5-3 in her career in WTA finals, the rest of those titles and finals all coming at International-level tournaments.
Also, Pavlyuchenkova's win over the World No.5 was her sixth Top 5 win. Her first five came at Indian Wells in 2009 (No.3 Jelena Jankovic), Tokyo in 2009 (No.3 Venus Williams), Beijing in 2009 (No.3 Venus Williams), the French Open in 2011 (No.3 Vera Zvonareva) and Brisbane in 2013 (No.5 Kerber).
Sharapova, who would have moved back to No.4 with the title this week, talked about the loss.
"I started the match really well, but as the match continued I wasn't doing the things that really helped me in the first set," she said. "I wasn't being aggressive, I wasn't in the court - she was playing with a lot of confidence in the match and I gave her that opportunity to step in and play her game.
"She was serving really well out there. She just played a really good match today."
And on the unfortunately-timed double faults? "They obviously came at the wrong time," Sharapova said. "When I was down in games in the first couple of sets I felt my serve really helped me, but in the third set I didn't keep that level up. I definitely need to improve that percentage going forward."
There's something very exciting coming up next for the Career Grand Slam holder though. "I'm heading to Sochi tomorrow for the Olympic Games," she said. Read more about her role there right here.