Daniil Medvedev powered his way past qualifier Aljaz Bedene on Wednesday to keep alive his chances of retaining the Western and Southern Open title.
Third seed Medvedev was too solid in a 6-3, 6-3 victory over 68 minutes for a place in the quarter-finals.
He will now play eighth seed Roberto Bautista Agut, who won their only previous meeting 6-3, 6-4 in the 2017 Chennai final.
“I returned much better than yesterday and was more solid,” Medvedev was quoted as saying on the ATP Tour website.
“To win by this score and quite easily against Aljaz is a big challenge.
“I got used to the conditions better today. It wasn’t easy for him as it was already his sixth match and I just took my chances. I don’t feel the courts are extra fast this year.
Medvedev broke twice in the 31-minute first set, with a backhand winner at 1-1, 0/40 and when Bedene hit a forehand into the net in the ninth game.
Medvedev won 90 per cent of his first-service points, while Bedene committed 16 unforced errors as the hot conditions in New York hindered the Slovenian.
Medvedev took a 3-1 lead in the second set and didn’t look back.
Bedene beat number 13 seed Cristian Garin and Taylor Fritz in his first two matches at the USTA Billie Jean King National Tennis Centre.
Bautista Agut did what he does best as the eighth seed competed with tremendous focus throughout to break down the hard hitting of number 11 seed Karen Khachanov in a 4-6, 6-3, 6-2 victory over two hours and six minutes.
Having lost the first set, Bautista Agut tightened up his game to frustrate Khachanov, winning the first three games of the second set and five of the first six in the decider.
The Spaniard, who hit 24 winners, clinched 14 of 18 points that went more than nine strokes for a place in the quarter-finals for the second year in a row.