After huffing and puffing through the opening week of the claycourt grand slam, the Spanish third seed was at his awe-inspiring best to set up a meeting with world number one Novak Djokovic in a rematch of last year's final.
"It's always been the case. The deeper I go the better I play usually. It's always been the case. It's the same this year. It's the same old story," Nadal told a news conference.
Djokovic, who subdued German 12th seed Tommy Haas in straight sets, beat Nadal in their last clash when the Serbian ended his rival's eight-year reign at the Monte Carlo Masters in the final in April.
Nadal, however, made it clear that Friday's clash would be nothing more than a semi-final match, even if the winner will be the hot favourite to lift the Musketeers Cup on Sunday.
"This is semi-finals, not finals. The one who wins this match to come will go through to the final, full stop. The others are Tsonga and Ferrer, full stop. End of story," he said.
Nadal, who has lost only one match at Roland Garros and has won five titles on clay this season on his return from a lengthy injury layoff, marched through the opening set, conceding no break points against a tiring Wawrinka.
The Swiss, who survived a five-set thriller in the previous round, ran out of steam and ideas, bowing out on the first match point after less than two hours.
"Today I played my best match of the tournament, it's very positive," a beaming Nadal, who finally enjoyed dry and warm weather conditions, said in a courtside interview.
SIMPLY UNBEATABLE
Wawrinka agreed that Nadal was simply unbeatable.
"It's the most difficult challenge to defeat Rafa at the French Open on the central court and with these conditions. They're excellent for him," he told a news conference.
"It's a lot faster and he can really have high balls on my backhand."
Nadal was asked why he always seems to peak as the Paris final looms.
"I don't control that, nobody does, it was not an easy first week," he said.
"I played better a bit against (Kei) Nishikori (in the fourth round) and today very well."
After dropping sets against German Daniel Brands and Slovakian Martin Klizan in the first two rounds, Nadal gradually found his best form.
It all went too fast for a red-faced Wawrinka on a sun-drenched Court Philippe Chatrier as Nadal showed his full array of massive pounding groundstrokes and high-bouncing top-spin shots.
Nadal, an 11-times grand-slam champion, had no mercy for Wawrinka, whose one-handed backhand seemed weak compared to the drilling shots of the Spaniard who bagged the first set with a commanding ace.
Wawrinka, who has not taken a set from Nadal in 10 matches, made his only break of the match in the second set, but it came after he had already lost his serve.
The fickle Paris crowd, supporting the ninth seed over their seven-times champion, love nothing more than an upset and they pretended they were smelling one, roaring their support for Wawrinka.
The defending champion quickly sealed a second break and Wawrinka struggled to even stay in his slipstream.
With sweat streaming down his face, Nadal made only two unforced errors as he blitzed through the final set.
