Feliciano Lopez has pulled off the upset…

The 33-year-old Spanish tenista took down No. 5 seed Kei Nishikori in straight sets to to reach the quarterfinals at the BNP Paribas Open on Wednesday.

Lopez pulled ahead in the first set, and then survived a hard-fought second set to win 6-4, 7-6 (2).

“I really had one bad game at 5-4,” Nishikori said. “Until then I was playing better. I was dominating the strokes. He was hitting good serves, but I had all the chances.”

Lopez reached the quarterfinals at Indian Wells for the first time in 13 tries. Lopez has previously been stretched to three sets in his first two matches.

He next faces Any Murray in the quarterfinals on Thursday.

Meanwhile, Rafael Nadal advanced with a 6-2, 6-4 victory over Gilles Simon to stay on track for a shot at his fourth career title in the desert.

Nadal next plays sixth-seeded Milos Raonic, who defeated 17th-seeded Tommy Robredo 6-3, 6-2 in a fourth-round match.

Nadal served a love game to close out his match that began as a dust storm swirled outside the stadium under overcast skies. He connected on 70 percent of his first serves in beating Simon for the seventh time in eight meetings.