Indian Wells, Mar 14: Juan Martin Del Potro continued his dominance over David Ferrer to book a spot in the Indian Wells fourth round as second seed Marin Cilic suffered a shock loss.

World No. 8 Del Potro extended his win streak over the Spaniard to five straight matches, winning 6-4, 7-6 (7/3) at the ATP Tour hardcourt tournament here Tuesday.

The 29-year-old Del Potro improved to 7-6 overall against Ferrer and his five consecutive victories dating back to the 2013 Wimbledon quarter-finals.

"We always play tough matches. I got lucky," said Del Potro. "I played really well in the tiebreak and served well in the important moments." Del Potro will next face fellow Argentinian Leonardo Mayer, who defeated Japanese qualifier Taro Daniel 6-4, 6-1.

Del Potro is playing some of his best tennis in years as he improved to 13-3 on the season. In January he returned the top 10 for the first time since 2014.

He is fresh off winning his 21st career title earlier this month in Acapulco when he steamrolled his way into the final by beating three top 10 players in a row. He capped off his Acapulco run by beating South Africa's Kevin Anderson 6-4, 6-4 in the championship game.

Del Potro, the 2013 Indian Wells finalist, hammered six aces and won 87 percent of his first-serve points in the one hour, 446-minute match against Ferrer.

He says he is eager to get back to the final and lift the trophy in the California desert. "It is one of my dreams to win this title. I have been in the final and the semis but I have never held the trophy," he said.

Elsewhere, world number three Cilic became another top seed casualty, losing in straight sets to Germany's Philipp Kohlschreiber 6-4, 6-4. The 29-year-old Cilic, who reached the finals of two of the last three Grand Slams, dropped to a record of 10-4 on the season.

Kohlschreiber advances to the fourth round where he will play unseeded Pierre-Hugues Herbert who won his third round match when fellow Frenchman Gael Monfils retired in the second set with a lower back injury.

Cilic blasted five aces but couldn't overcome Kohlschreiber's strong serving game. The German won 76 percent of his first serve points and broke Cilic's serve twice, once in each set.

- Played aggressively -

Kohlschreiber said he tried to get the match over as quickly as possible. "I felt good. I played aggressively I played well in the crucial moments and on the big points," Kohlschreiber said. "I think another key factor was that it was a two-set win."

Kohlschreiber is now 7-4 overall against Cilic. He has won three out of their last four meetings, including a straight set victory in the final in Munich on clay in 2012. He won their first meeting on hardcourt in Moscow in 2007.

In other third round matches, Canadian No. 1 Milos Raonic beat Portugal's Joao Sousa 7-5, 4-6, 6-2 and Sam Querrey of the United States rallied to outlast Yuki Bhambri 6-7 (4/7), 6-4, 6-4.