Ranked 38th in the world, Tsonga will face either defending champion Roger Federer or world No. 3 Novak Djokovic in Sunday's decider after stunning triple French Open winner Nadal 6-2 6-3 6-2. Tsonga has monstered a host of better-credentialled foes to steam into his first major final.
The Muhammad Ali lookalike blew world No. 2 Nadal to smithereens, burying nerves and fear under a veneer of drilled groundstrokes, massive serves and delicate drop volleys.
Tsonga clubbed 49 magnificent winners to strangely ineffectual Nadal's 13, closing out the match with his 17th ace after 117 minutes.
Blinking in disbelief, Tsonga jigged briefly on centre court as his coach Eric Winogradsky fought back tears.
"It's unbelievable, three sets, it's just amazing," Tsonga said.
"I don't know what to say. Today I played unbelievable, and nothing can stop me and I am just happy.
"It's like a dream. Every day, this like a dream. I can't believe it's true, just amazing."
The son of a chemistry teacher who played international handball for Congo, Tsonga continues Melbourne Park's habit of plucking moderately performed competitors and plonking them in the spotlight.
Chilean Fernando Gonzalez, Cypriot Marcos Baghdatis, German Rainer Schuettler and Swede Thomas Johansson, the 2002 champion, defied the odds to excel at Rod Laver Arena during the past six years.
Powerfully built, Tsonga, 22, hammered his way past seeds Andy Murray, Richard Gasquet and Mikhail Youzhny to earn a crack at Nadal - and he was undaunted by the rarified atmosphere last night.
He will on Sunday attempt to become only the second Frenchman in history to claim the Australian title and the first since Jean Borotra in 1928.
And he will do so as the eighth-lowest ranked finalist at the Australian Open.
Expressive, emotional and animated, Tsonga threw everything at Nadal.
The injuries that all but wrecked his dream of becoming a top-line player seemed a lifetime ago as he dictated terms to the sport's best counter-puncher.
When it was over, it appeared no one - including both players - could believe it. But Tsonga was already looking ahead.
"Both of them (Federer and Djokovic) have two arms, two legs like me," he said of Sunday's final.
"I'll do my best."