By Martyn Herman
The 28-year-old Russian has suffered so many near misses at grand slams during her long career that she could be excused for thinking her time to win one will never arrive.
Instead, she just keeps on turning up hoping that one day Lady Luck will be on her side.
Dementieva advanced to her ninth grand slam semi-final with a 2-6 6-2 6-0 victory over fellow Russian Nadia Petrova, another player running out of time to land her first major.
In steady rain on Court Suzanne Lenglen, fifth seed Dementieva made a shaky start but with Petrova increasingly bothered by a thigh injury she eased to victory.
She will now face Italy's Francesca Schiavone to reach her third grand slam final, the other two coming in 2004 when she was runner-up at Roland Garros and at the U.S. Open.
"For sure it's on my mind," Dementieva, whose career highlight was winning the 2008 Olympics, said when asked if the "nearly girl" tag bothered her.
"Winning a grand slam is one of the biggest goals left in my career and it's a great motivation for me," she said.
"But coming into the grand slams I'm not thinking about my chances. I'm not thinking this has to be the one.
"I'm just trying to take one match at a time, build my game and play my best. You can't think about winning it. It's a two-week competition and anything can happen.
"I'm just glad to be in the semi-finals and let's see if I can handle this challenge."
This year's French Open is her 46th consecutive grand slam appearance since, more than any other active player.
Should she manage two more victories here she would break Jana Novotna's record for dogged persistence, the Czech finally breaking her duck on her 45th at Wimbledon in 1998.
Some days all that experience pays off.
Niggled by a thigh injury of her own and with rain dampening the Parisian clay, Dementieva took a while to find her range from the baseline. Her serve was also erratic.
After resuming play having received treatment at 2-3 in the first set she immediately lost the next three games but she did not panic and once she broke early in the second she quickly got on top of an opponent who twice needed the trainer.
Petrova, who had won half of their previous 14 meetings dating back to 1997, believed she had been in with a great chance before her injury worsened.
"I won the first set comfortably. But I was limited out there, I was not moving properly. I was not able to chase all the balls. But I don't like quitting. I like to finish till the end even if I'm not 100 percent."
(Editing by Justin Palmer)