Casper Ruud was a surprise second-round loser as the Swedish Open defending champion fell to Francisco Cerundolo, while the favourites battled through at the Hall of Fame Open.

Ruud, a French Open finalist and defending champion in Bastad , lacked his usual composure as world number 39 Cerundolo broke him three times to win 6-4 3-6 7-5 on Wednesday.

That marked a first top-10 career victory for Cerundolo after defeating world number five Ruud, guiding him to his first quarter-final appearance at the tournament.

"I'm feeling amazing, I'm really happy," said Cerundolo, whose previous best result was beating world number 24 Gael Monfils. "It's amazing getting my first Top 10 win. It's been the best year so far in my career.

"He's a French Open finalist and was the defending champion here, so it was a big challenge for me and I'm happy to go through."

Aslan Karatsev awaits in the quarter-finals Cerundolo after downing Frenchman Hugo Gaston 6-2 6-4.

Fifth seed Pablo Carreno Busta survived a first-set scare to defeat 2016 champion Albert Ramos-Vinolas 4-6 7-6 (7-5) 7-5.

The victory was Carreno Busta's 250th tour-level triumph and he will next face third favourite Diego Schwartzman, who overcame Elias Ymer in straight sets.

Third seed Alexander Bublik was made to work for a 6-3 3-6 6-2 second-round victory over Jack Sock in Newport and Andy Murray edged past Wimbledon doubles champion Max Purcell.

Murray needed almost two-and-a-half hours to get the better of Purcell, eventually triumphing 4-6 6-2 6-1 to tee up a last-eight meeting with Bublik.

Fourth favourite Maxime Cressy had little trouble in beating fellow American Mitchell Krueger 6-3 6-4 and will next face Steve Johnson, who progressed past seventh seed Jiri Vesely with a walkover.

Benjamin Bonzi, ranked as fifth seed in the United States, eased past Christopher Eubanks in straight sets, while James Duckworth triumphed 7-5 3-6 6-2 over Quentin Halys.

John Isner joined the list of favourites who made the third round in routine fashion, beating Peter Gojowczyk in straight sets 6-3 7-6 (8-6), before top seed Felix Auger-Aliassime faced some adversity against Jason Kubler following the Australian's strong run into the fourth round of Wimbledon.

Auger-Aliassime has a slight advantage, leading 6-4 3-6 6-5 before play was suspended due to poor light. When play resumes, Kubler will serve with a chance to force a third-set tiebreak.