​Coco Gauff celebrates after defeating fellow American Iva Jovic 6-1, 6-4 to reach the US Open quarter-finals.Photograph: Cristóbal Herrera/EPACoco Gauff continued her serene march through the US Open women’s draw with her most complete performance yet on Monday night, seeing off fellow American Iva Jovic 6-1, 6-4 to reach the last eight in New York for the first time since winning it all in her grand slam breakthrough three years ago.Related: Zheng Qinwen erases another 5-0 deficit to stun Swiatek and reach US Open quarter-finalsThe fourth-seeded Gauff overwhelmed Jovic with the depth of her returns and an assured blend of aggression and defense, finishing with twice as many winners (18 to nine) and half as many unforced errors (15 to 30). The 1hr 20min clinic was the latest statement in a late-summer win streak that has transformed her from a player searching for answers this time last year into perhaps the most dangerous woman remaining in the field.Next comes a delicious quarter-final clash with Mirra Andreeva, the reigning French Open champion and fifth seed, after the 19-year-old Russian came from behind to defeat Anastasia Potapova 5-7, 6-4, 6-3 in Monday’s day session.“The biggest difference in the way I’ve been playing is just trying to play with no regrets,” Gauff said afterwards. “I think I have a lot more fun and success playing like this.”The 22-year-old arrived in New York fresh off her first title of the year in Cincinnati and had yet to drop a set throughout the first week, but Monday’s task with barely an empty seat inside Arthur Ashe Stadium represented her stiffest examination yet.Jovic, the 18-year-old from Los Angeles seeded 14th, has been tabbed as one of the brightest prospects in US tennis since crashing the Australian Open quarter-finals in January ahead of fourth-round runs at both Roland Garros and Wimbledon, which made her the youngest American to reach the second week at three majors in a season since Venus Williams in 1998. She had punched her ticket to the last 16 after a grueling three-hour win over breakout star Alexandra Eala in a Saturday night blockbuster, fighting back from 2-4 down in the deciding set to prevail 7-5, 3-6, 7-5.Related: Will hordes of influencers, weed smokers and mid-point talkers bring down the US Open?Gauff knew first-hand what sort of resistance to expect. Their only previous meeting on tour, at the Rome Open in May, required nearly three hours and a comeback from a set down before Gauff escaped 5-7, 7-5, 6-2 after saving a match point. “I think that experience helped me for today,” Gauff said. “I knew to expect that she was going to be at 100 from the first point to the last.”This time there was considerably less drama. After opening with a tense 11-minute exchange of breaks, Gauff never let Jovic get comfortable, taking the ball early off both wings and peeling off six straight games to take the opening set in 33 minutes.Jovic finally interrupted Gauff’s momentum