Raducanu upset the odds to become the first qualifier to win a grand slam during the Open era on Saturday, beating fellow teenager Leylah Fernandez in the final at Flushing Meadows.
Her breathtaking performances in New York came off the back of a promising debut at Wimbledon just two months before, where she reached the fourth round before withdrawing with “breathing difficulties.”
“Totally unexpected. Never thought it would happen in my lifetime to see an 18 and 19-year-old do it,” McEnroe told CNN’s Christiane Amanpour, speaking of the all-teen final at the US Open.
“I think the women’s game is more open than it’s ever been so that’s a sign that a lot more players think they have a chance.
“I can’t imagine anyone in her [Raducanu] camp expected this. To win the US Open without losing a set, that’s crazy. She’s a tremendous athlete, she seems like a great kid.”