“Ilie was quite a bit older and sort of at the end of the line,” said McEnroe, who had lost to him three times but had beaten him the last two times they played.

“The truth is, he saw pretty early in the match that things weren’t going to work out for him on court, so he just figured he would take it to the limit. I don’t recall doing anything, actually. That was one of the best-behaved matches I ever played.”

Mary Carillo , McEnroe’s friend and onetime mixed doubles partner, was also in the stands.

“I thought there would be nonsense that night, but I never expected mayhem,” said Carillo, now a Tennis Channel analyst, in addition to working for NBC and HBO Sports. “Nastase created all the chaos. John was, shockingly, the good one. But New York has a special energy, and the fans were more than willing to jump into the fray.”

The chaos started early in the fourth set with McEnroe leading by two sets to one and serving at 15-0 . It was nearing midnight. After Nastase inexplicably flicked off the cap of the net-cord judge, he sauntered to the baseline, but simply stood there.

“I was tired,” said Nastase, 73, by phone from his home in Romania last month . “I was 33 already and not playing much anymore. He was 20. I had to pull out all the tricks.”