After storming out to a 3-0 lead, Cibulkova watched as the No.11-seeded Simona Halep closed the gap, winning three of the next four games to make it 4-3. But from there the No.20-seeded Cibulkova didn't even lose another game, reeling off eight straight to close it out in exactly an hour, 63 60.
Cibulkova has now scored three upsets in a row - No.16 seed Carla Suárez Navarro, No.3 seed Maria Sharapova and No.11 seed Halep - to go this far at a major for the second time. At Roland Garros in 2009 she made it this far too, falling in straight sets to the eventual runner-up, Dinara Safina.
"I'm really glad with the way I played, especially with the way I handled it mentally, after a big win over Maria," Cibulkova said. "I wasn't the favorite in this match against Halep either, but I walked on the court with the confidence I could do it again today. I was focusing on what I had to do, to do the right things. That was all I wanted to do out there, and of course enjoy my tennis on the court again."
Did her being in Grand Slam quarterfinals before and Halep not make any difference?
"I think it was important that I was already on this stage before," Cibulkova said. "I already played a couple of quarterfinals at Grand Slams, and I already did the semifinals at a Grand Slam, so that was important experience today. I didn't take it too seriously and didn't put myself under pressure."
"I just couldn't play today," Halep said. "I had big emotions and couldn't manage it. Before the match I was very nervous and I didn't feel the ball at all. I couldn't move my body and I couldn't play.
"But she played really well, she hit all the balls very strong and moved really well."
Cibulkova's French Open semi was almost five years ago - she says things have changed since then.
"I was 19 years old then," Cibulkova said. "I was pretty young. I would also say I was a different player. Now I'm much more experienced and have gone through so many things in my career since then.
"I would say I'm more mature now."
Despite the loss, Halep still had the best Grand Slam of her career - a win over No.8 seed Jelena Jankovic in the fourth round, her first quarterfinal at a major - she leaves on a very positive note.
"I'm happy I could play a quarterfinal here at a Grand Slam. It was my dream before this. I don't want to disturb my mind with this match today - I just want to enjoy the day and go home very happy.
"I will have many chances to pass the quarterfinals in Grand Slams, but I have to work hard like I have been. And I want to be prepared before the big matches. So I have to work - hard work."