Wawrinka overcame blisters, searing heat and a threatening mid-match fightback from 14th seed Jo-Wilfried Tsonga to prevail 6-3 6-7 (1-7) 7-6 (7-3) 6-4 in a tense three-hour, 46-minute battle on Court Philippe Chatrier.
Tsonga will rue squandering 16 of 17 break-point chances as he looked to become the first Frenchman since Yannick Noah in 1983 to hoist the Musketeers Cup.
Just five tournaments into his comeback, Tsonga was bidding to venture at least one step further than his 2013 semifinal loss in Paris to David Ferrer.
Wawrinka crunched 16 aces and 60 clean winners to shatter Tsonga on a big stage for the second time in seven months. He also beat Tsonga in the opening rubber of Switzerland's Davis Cup final victory over France last November before the Frenchman was sidelined until March with a forearm injury.
Wawrinka required treatment for blisters on his racquet hand after holding for 2-1 and then sought another medical during the following changeover.
But he soldiered on, claiming the pivotal third-set tiebreaker. A crucial third service break early in the fourth set put Tsonga on the ropes.
Wawrinka finally progressed to the final on his 11th trip to Paris when Tsonga dumped a forehand return into the net on the Swiss's first match point.
"I have been really focused on the way I'm playing, on the way I'm dealing mentally with my pressure, with the way I want to go into this tournament. Jo is always a tough player to play, especially when he's playing at home here in Paris."
So tough is Tsonga that he claimed the prize scalps of Djokovic, Murray and Federer to win last year's Toronto Masters.
But after losing his fifth consecutive grand slam semifinal since falling to Djokovic in the 2008 Australian Open decider, the Frenchman has no doubts Wawrinka can go all the way at Roland Garros.
"He did it once, so why not?" Tsonga said.
Wawrinka is the first player since eventual champion Albert Costa in 2002 to make the final after crashing out in the opening round the previous year.
Now 'Stan the Man' can hardly believe he has the chance to become the first former junior champion at Roland Garros to win the men's crown since Mats Wilander in 1982.
"My dream was to play Roland Garros, not to win it, not to reach the final," Wawrinka said. "The fact that I have reached the final now here is something exceptional after winning a grand slam in Australia a year ago. And to think that this is yet another final in yet another grand slam, it's something amazing."
Wawrinka will play either the top-ranked Djokovic or third-seeded Murray for the title.
Djokovic was leading 6-3 6-3 5-7 3-3 when the grand slam titans had their semifinal suspended yesterday because of a severe storm warning in Paris.
- AAP
