Germany rallied to win the United Cup 2-1 over top seeds Poland on Sunday in Sydney, after another extraordinary escape act, this time from Alexander Zverev. The Olympic champion saved two Polish championship points in a second-set tie-break for a 6-7 (3-7), 7-6 (8-6), 6-4 triumph against Hubert Hurcacz, which levelled the tie at 1-1 after Iga Swiatek beat Angelique Kerber 6-3, 6-0 in the opening rubber. Zverev then teamed up with Laura Siegemund to win the deciding mixed doubles, 6-4, 5-7, 10-4 well after midnight, wrapping up matters with a backhand volley. World number six Zverev showed ext…