Where did that come from?
Alexander Zverev staged an extraordinary comeback in the first of Friday's two US Open semifinals, beating Pablo Carreno Busta 3-6, 2-6, 6-3, 6-4, 6-3 at Arthur Ashe Stadium.
The fifth-seeded German was uncharacteristically weak on his backhand for prolonged spells and surrendered 22 unforced errors in the second set alone, but fought back from a two-set deficit.
Zverev will face either Daniil Medvedev or Dominic Thiem in Sunday's final. It wasn't pretty, but Zverev is one match away from capturing his maiden Grand Slam crown. The semifinal marked the first time he's rallied back from two sets down to win in his career.
"I'm through to my first Grand Slam final and that's all that matters," Zverev said after his victory, according to BBC Sport.