Swiss third seed Wawrinka, the 2015 title victor, has not lost a set on his way to a third successive semi-final in Paris.
But the second set proved the turning point for the double Olympic gold medallist, levelling up the match with the tennis that has taken him to top spot in the world with a 6-1 set.
The world number one struggled with his opponent's explosive baseline hitting on Philippe Chatrier, but slowly warmed to his task in windy conditions as he secured a 2-6 6-1 7-6 (0) 6-1 victory.
"Last year, I was playing really well and I was confident, but I remember that he played better than me on that court", he said.
The Japanese twice came from behind in a third set that ebbed and flowed, only to surrender meekly during the subsequent breaker.
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"I think that was probably the best I have played overall [at the tournament]", said last year's runner-up. "I think physically and mentally I feel ready", he said.
Meanwhile, Simona Halep staged a remarkable fightback and saved a match point to reach the semi-final with a 3-6 7-6 (6) 6-0 win over Elina Svitolina yesterday. All four players are seeking a first grand slam title.
The Portuguese official has also had a run-in with Novak Djokovic. His 100-2 record includes his only pair of Roland Garros defeats: against Robin Soderling in the 2009 fourth round and Djokovic in the 2015 quarterfinals. The 23-year-old Austrian beat Nadal last month in Rome in the Spaniard's only loss on clay this season. In another quarterfinal, Pliskova meets No. 28 Caroline Garcia, a 6-2, 6-4 victor against Alize Cornet in a match between two Frenchwomen.
Murray was barely tested in the fourth round, beating 21-year-old Karen Khachanov 6-3, 6-4, 6-4.
Wawrinka, 32, is now the oldest semifinalist at Roland-Garros since Jimmy Connors in 1985. Djokovic, the defending champion, takes on No. 6 Dominic Thiem of Austria at Court Suzanne Lenglen in a rematch of a 2016 semifinal at Roland Garros that Djokovic won in straight sets.
Wawrinka, who crushed Marin Cilic 6-3, 6-3, 6-1 in yesterday's quarter-finals, is a late developer.