World No. 7 Alexander Zverev produced a heroic performance to lift Germany past Iga Swiatek’s Poland in a dramatic final at the United Cup in Sydney.

After the top-ranked Swiatek had brushed aside Angelique Kerber in straight sets, Zverev leveled the final as he overcame two match points and fatigue to beat Hubert Hurkacz 6-7 (3), 7-6 (6), 6-4 in a three-hour thriller.

Zverev then teamed up with Laura Siegemund to down Swiatek and Hurkacz 6-4, 5-7, 10-4 as Germany won its first United Cup title in the early hours of Monday morning, Xinhua reports.

An indefatigable Zverev showed superb fitness and mental strength after backing up from a grueling semifinal against Australia, where he lost in three sets to Alex de Minaur before helping Germany clinch the decisive mixed doubles at 2.20am local time on Sunday.

Swiatek had given Poland the lead after she won her fifth straight match of the tournament with a convincing 6-3, 6-0 victory over former world No. 1 Kerber at Ken Rosewall Arena.

The 22-year-old Swiatek claimed her 16th consecutive win stretching back to a strong finish last year when she emerged victorious at the China Open and season-ending WTA Finals in Mexico.

Swiatek has already racked up four Grand Slam titles, but has never reached the final of the Australian Open with her best result being a semifinal finish in 2022.

The Pole thwarted an early challenge from Kerber, who continued her return from an 18-month layoff due to maternity leave.

Kerber came out swinging in a see-saw first set before Swiatek stepped up her level and took control to cruise to victory in 70 minutes.

“I’m really proud of myself that I could win all my singles,” Swiatek said. “[Kerber] was really picking the right spot to play and she surprised me sometimes at the beginning of the set with her decision-making and choices.

“I felt like my game can be more dynamic, and I just pushed Angelique a bit more after it was four-three [in the first set].”

Germany’s title hopes rested with Zverev, and he proved he had plenty left in the tank as he went toe-to-toe with No. 9 Hurkacz in a tense first set. Hurkacz lifted in the tiebreak to draw first blood, and he hoped to power away from a presumably tired Zverev.

But the big-hitting German produced a gutsy effort and saved two match points in the tiebreak, the first through an incredible crosscourt forehand winner at 6-4 down. He forced a deciding set and found a way to clinch a memorable victory despite looking gassed on several occasions.

“I was exhausted,” Zverev said. “In the middle of the second set I was already exhausted and in the third set I was hanging on a lot of the time and somehow got the break.”