Nadal set up a last eight meeting with Wawrinka by beating Frances Tiafoe 6-3 6-4 on Court Manolo Santana.
The Spaniard is yet to win a trophy this year and his drought goes back to last August but the 32-year-old has looked in confident mood in his opening two matches of the tournament.
And he will start the match against Wawrinka as the favourite with his 17-3 winning head-to-head record.
Speaking after his win over Tiafoe, Nadal was asked for his assessment of the clash with Wawrinka and the 17-time Grand Slam champion says he will need to be at his best.
“It’s a tough one,” Nadal told the ATP.
“He’s one of the best players in the world and he likes to play in these conditions.
“It’s fast, at altitude. He’s got a big serve, big shots.
“So it’s the kind of match where I need to play my best. And hope to be ready to make that happen.”
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