Iga Swiatek survived a two-hour and 57-minute thriller against Katie Boulter after completing a 6-7 (3) 6-1 6-4 win at the United Cup to help Poland seal a semifinal ticket at the event. Although the 24th-ranked Briton entered as the underdog,

The British number one had a break point at 4-4 in the deciding set against Poland’s five-time grand slam winner.

In Sydney, Italy earlier won Group D to qualify for the quarterfinals. Winners of the past two Davis Cups and runners-up two years ago to the U.S. in the inaugural edition of the season-opening mixed teams’ event, Italy won its group without world No.1 Jannik Sinner.

Poland returned to the semi-finals of the United Cup mixed team tournament for a third successive year after hard-fought singles victories in Sydney handed them an unassailable 2-0 lead over Britain on Thursday.