Newport, Rhode Island , 11 July 2013 | AAP

Lleyton Hewitt has strolled into the quarterfinals of the Hall of Fame Tennis Championships after brushing aside former finalist Prakash Amritraj in straight sets.

The No.4 seed capitalised on five of his six break points to beat the Indian 6-2 6-1 in the US city of Newport on Wednesday.

But Hewitt, a runner-up at last year’s tournament, said the match was a lot closer than the score reflected.

“I felt I played well in the key moments – grass-court tennis is like that,” he told the ATP website.

“It’s only two or three points sometimes in a set can change the whole match.”

The 32-year-old will next face Czech qualifier Jan Hernych, who proved too good for American Jack Sock.

John Isner, who retired in the second round at Wimbledon last month with a knee injury, extended his 12-match winning streak at Newport with a 6-0 7-6 victory over Frenchman Adrian Mannarin.

Isner will meet Ivo Karlovic in the quarter-finals, after he saw off Canada’s Vasek Popisil in three topsy-turvy sets 6-1 1-6 6-3.

Michael Russell beat Alex Kuznetsov 6-3 6-4, while American Rajeev Ram went down in three to Michal Przysiezny.

Meanwhile fellow Australian Matthew Ebden, whom Hewitt beat in their round one singles clash, fared better in the men’s doubles.

Ebden and Igor Sijsling of the Netherlands beat Venezuela’s Eduardo Gil and American partner Krasimir Kolev 6-2 6-1 to advance to the second round.