Rafael Nadal has advanced to the quarter-finals of the ATP Masters 1000 event at Indian Wells with a routine win over qualifier Filip Krajinovic 6-3, 6-4.

World No.2 Nadal dropped his serve once in a 6-3 6-3 victory on a sunny and windy Wednesday.

Nadal remains on track for a potential semi-final against five-time champion Roger Federer in the bottom half of the draw.

The top half was rocked by the upsets of top-ranked Novak Djokovic and No. 3 seed Alexander Zverev on Tuesday.

The difference between players is not huge. It’s small gaps,” Nadal said about the upsets.

“It’s true that for the last 10 years didn’t happen very often.”

Krajinovic hadn’t dropped a set in winning his first three main-draw matches after two wins in qualifying but he was outclassed by Nadal in their one hour and 26 minute encounter.

“Probably played a little bit worse today than yesterday,” Nadal said.

“Maybe because of the conditions.”

Next up for Nadal is the winner of a fourth-round match between John Isner and Karen Khachanov while Federer will face Briton Kyle Edmund in the round of 16.

Meanwhile, Miomir Kecmanovic, a 19-year-old Serb ranked world No.130, to the last eight when Yoshihito Nishioka of Japan retired after he losing the first set 6-4.

Kecmanovic became the first lucky loser to reach the quarter-finals since the tournament achieved Masters 1000 status in 1990.

“It will be funny that somebody other than Novak is still in,” he said of his famous countryman.

Kecmanovic got into the main draw when world No.6 Kevin Anderson withdrew before his opening match with an elbow injury.

Canadian Milos Raonic will be Kecmanovic’s next opponent after the big-serving 13th seed accounted for German Jan-Lennard Struff 6-4 6-3.

Raonic broke serve once ine ach set and fired down 12 aces in the 74-minute match.