Sydney ¨C Poland returned to the semifinals of the United Cup mixed team tournament for the third straight year after hard-fought singles victories handed it an unassailable 2-0 lead over Britain in Sydney on Thursday.

Iga Swiatek settled the tie after an almighty battle with Katie Boulter, prevailing 6-7 (4-7), 6-1, 6-4 as last year¡¯s runner-up booked a last-four clash with Kazakhstan in the $10 million tournament.

¡°I¡¯m just exhausted,¡± Swiatek said after the nearly three-hour marathon at Ken Rosewall Arena. ¡°I¡¯m happy that I won, so that I don¡¯t need to play mixed doubles. This match was crazy, so many changes of momentum.¡±

Swiatek squandered a 4-1 lead in the opening set, which her opponent clinched in 74 minutes after an inspired comeback.

But the world No. 2 was not to be denied as she romped through the second set and shrugged off a right leg issue in the decider to outlast Boulter.

¡°I thought I had it under control in the first set, but I got tight,¡± Swiatek said. ¡°I didn¡¯t want to repeat the same mistake in the third, and I took four pain killers.

¡°A lot hurt, but I¡¯m happy that I won and, for sure I¡¯m going to need the day off tomorrow.

¡°If they give me space to lie down (in the dugout) I¡¯ll take a nap ... I think I¡¯ll just go to the locker and die.¡±

Poland¡¯s Hubert Hurkacz clinched a tight opening set when Billy Harris sent a backhand long in the tiebreak and then raised his game late in the second set to seal a 7-6 (7-3), 7-5 victory to put his team ahead 1-0 in front of delighted fans.

¡°Definitely super pleased with myself,¡± Hurkacz said after his first singles win of the tournament.

¡°Today was a really difficult battle with Billy ... This win is so crucial to get more confidence and get another match in.¡±

The United States, the 2023 champion, has already reached the semifinals and face the winner of Friday¡¯s quarterfinal clash between Italy and the Czech Republic.

The final takes place on Sunday.