SYDNEY: World number two Iga Swiatek was a comfortable winner as Poland reached the United Cup quarter-finals while Coco Gauff also eased to victory for defending champions the United States on Wednesday. Six-time Grand Slam champion Swiatek beat 97th-ranked Suzan Lamens 6-3, 6-2 in the tie against the Netherlands in Sydney. Hubert Hurkacz, on his way back after being out for seven months following knee surgery, defeated Tallon Griekspoor 6-3, 7-6 (7/4) as Poland sealed their last-eight spot. Poland will face hosts Australia on Friday. In Perth, world number four Gauff put the United States ahead in their quarter-final against Greece with a 6-3, 6-2 win over former number three Maria Sakkari. The 21-year-old Gauff struggled with her serve as she suffered her first-ever defeat at the United Cup on Monday when she was stunned by Spain’s Jessica Bouzas Maneiro. “Definitely a much better match today,” Gauff said after making light work of Sakkari. “Last match, I just tried to erase it. That’s the beauty of this tournament. “So definitely happy to give my team the lead today.” The mixed-team United Cup features 18 teams and serves as build-up towards the Australian Open, which starts on January 18.