Alexander Zverev has survived an extraordinary meltdown to sink Tommy Paul in four sets and charge into the Australian Open semi-finals.

Second-seeded Zverev, chasing an elusive grand slam title, was almost knocked down by, of all things, a feather before he steadied to prevail 7-6 (1), 7-6 (0), 2-6, 6-1. Zverev will next face either world No 3 Carlos Alcaraz or 10-time champion Novak Djokovic, who play on Tuesday night, in his third Melbourne Park semi-final.

“To be honest, I should have been down two sets to love, he served (for) both of those sets. He played better than me,” Zverev said. “I was not playing great and I thought he was. I somehow won the first set, somehow won the second set, [then] I’m up two sets to love all of a sudden and I only need one more set. The fourth set was definitely the best that I’ve played and I’m obviously extremely happy to be back in the semi-finals.”

Tennis’ biggest unfulfilled talent, with two grand slam final losses to his name, Zverev won the first set in a tiebreak, fighting back after Paul served for the set at 6-5. But with a serving Paul leading the second set 4-2, Zverev had his feathers ruffled – then almost imploded.

On break point, the German was incensed at the chair umpire after someone in the crowd yelled out just as he was about to swing at a ball close to the line – making him believe it had been called out. No action was taken. The 27-year-old then dropped the following point and received a code violation for an audible obscenity.

Then, at deuce, the umpire called a let after a feather landed near the ball just as Zverev was about to hit it. It meant the point was replayed and Paul received another first serve. Zverev plucked the feather – courtesy of one of the many seagulls in the Rod Laver Arena rafters – from the court and brandished it at the umpire in frustration.

“Buddy, it’s a feather!” Zverev said. “There’s millions of them on the court.”

But rather than implode, the German was unflappable as he forced the set to a tiebreak. Paul, 27, served for the set at 5-3 and earned a set point on Zverev’s serve when leading 5-4, but couldn’t take his chances and was broken. The German demolished the American 12th seed 7-0 in the tiebreak.

Paul again recovered, breaking Zverev early in the third set and teeing up three set points on serve at 5-2, and this time converting. It proved only a brief setback for Zverev, who cruised through the fourth set to claim victory.